"Risk determination not possible" - wrong info

[Jo-Achim]

I've read this topic here before - but I can't find it right now, sorry.

Android 10 with Android security update: July 1st, 2020
Nokia 7.1, Build: 00WW_4_15C_SP02
NetGuard: 2.287
Internet: WLAN (only)
CWA version: 1.2.1

Problem: "Risk determination not possible" is displayed although the risk determination is active; see screenshots.

General condition: The last CWA data exchange took place on 08/24/2020 at 7:38 am (thereafter no more internet connections until 08/26/2020).
The next time the CWA was started (with internet connection) on August 26, 2020 at around 7:08 pm / 7:09 pm, the incorrect risk determination information was displayed:

After [->] the updated, correct data including the risk assessment were displayed:

Best regards.

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Internal Tracking ID: EXPOSUREAPP-2795
Internal Tracking ID: EXPOSUREAPP-2796

[MikeMcC399]

Hi @Jo-Achim,

The issue is that the status "RISIKO-ERMITTLUNG AKTIV" is contradictory to the button "RISIKO-ERMITTLUNG EINSCHALTEN". If Exposure Logging is already active then there is no need to switch Exposure Logging on and the user should not be prompted to do so. That presents a confusing message to the user.

It's OK for a temporary status "Risiko-Ermittlung nicht möglich" if the app cannot pull the diagnosis keys from the server when it tries. That status was cleared and replaced by "Niedriges Risiko" after the diagnosis keys were fetched and compared to the keys on the mobile device.

[Jo-Achim]

Hi @MikeMcC399,

yes, on the one hand I wanted to draw your attention to the fact that at least the information "switch on risk determination" when "risk determination is switched on" is wrong.

On the other hand, I believe that the message "Risk determination not possible" / "Risiko-Ermittlung nicht möglich" should not appear at all if the diagnostic keys were exchanged in the background at the same time. Because in this case the info is irrelevant.
It would be different if no diagnostic data could be exchanged again with the current CWA call.

Best regards.

[MikeMcC399]

@Jo-Achim

On the other hand, I believe that the message "Risk determination not possible" / "Risiko-Ermittlung nicht möglich" should not appear at all if the diagnostic keys were exchanged in the background at the same time. Because in this case the info is irrelevant.
It would be different if no diagnostic data could be exchanged again with the current CWA call.

I get your point. If I understood you correctly, in order to get the "Niedriges Risiko" screen to appear you had to tap on the arrow on the "Risiko-Ermittlung nicht möglich" screen. If the screen refreshed automatically (from "Risiko-Ermittlung nicht möglich" to "Niedriges Risiko") without your user action, that would be OK, but if you had to tap the arrow to get an updated status then that is not so good.

We probably have to wait for some comment from the support team / developers now for the two points raised by your issue.

[Marco2907]

Hello, @Jo-Achim thanks for your feedback. I will keep both points to our development support and will give an update as soon as possible.

Best,
MP

Corona-Warn-App Open Source Team

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Internal Tracking ID: EXPOSUREAPP-2393

[bufemc]

I have exactly the same screen, even with same date (24th August). Since days it will not work, but if I try to re-trigger it I get always this: see screenshots below. Phone is a LG G4, Android 6.0, CWA app was updated today, so version is the recent one. Meanwhile I really think the only way out is to re-install the app.. but would it help?

Regarding: https://www.coronawarn.app/de/faq/#API10 I have version 16203302004 of Covid protocol.

I guess for normal human beings (so, not nerds) this is a no-go, they might de-install the app ("it does not work!").

[daimpi]

@bufemc
The error you're getting (39508) is a rate-limiting error, i.e. your app was trying to access a certain API functionality too frequently today. Normally what helps in such circumstances: stop the app -> wait for 24h -> open the app again.
The reason is that the limits are reset once a day, after which everything should work fine again :)

Could you try this and check whether your app can sync after this?

The tracking issue for this problem can be found here: #1021

Btw: CWA 1.3.0 has just been released in the Play-store. Maybe you want to update before you wait the 24h 🙂.

[vaubaehn]

Hi @bufemc , I'm also running an LG G4, only very rarely problems occur for me...
One possible reason in your case - are you shutting down your phone in the nights, or enable flight mode?

[vaubaehn]

@daimpi ; you can now easily find out the version of CWA by closely looking to the 39508 error message: now the 39508 is not part of the link to the FAQ anymore, so the user ends up at the top of the FAQ (introduced with #1007). But don't worry, in version 1.4.0, the 39508 will again be part of the link to the FAQ, this time in the format .../faq/#39508 (see #1074).
😆

[bufemc]

@daimpi thanks, will try this to overcome "The error you're getting (39508) is a rate-limiting error".
UPDATE: and yep, you are right. Today it works. However I wonder how the limit could be reached although the phone was off for several days before, I described this in German in #1119

@vaubaehn yep, this is a phone which is most times off, sometimes for days.. it's used only for particular reasons, but then this app denies to work..

for this 39508 code.. I suggest to add an explaining text then, like "limits reached" or whatever, again, for normal human beings ,)

[svengabr]

I am happy to announce that the error 39508 is well known by the development team and a fix is going to be rolled out within the next days with the hotfix release 1.3.1.

There are currently many issues opened regarding the 39508 issues. If you want to contribute to the existing discussion, please use the main issue here.

• CAUSE: 3 Something went wrong. ApiException: 39508 #1021
• Resetting the CWA triggers error 39508 #934
• Risikostatus wird nicht aktualisiert #1119
• Fehler bei Kommunikation mit Google API (39508) #774
• Auf Samsung Handy seit 2 Wochen Fehlermeldung 39508 #1130
• Google APIException (39508) after using the SwissCovid App #816

Best regards,
SG

Corona-Warn-App Open Source Team

[traut21]

So when does the next update happen? Your comment is 7 days old by now.

The error warning is annoying and does destroy trust into the proper operation of the app.

[vaubaehn]

Hi @svengabr ,

I'd like to underline, what @traut21 wrote:

The error warning is annoying and does destroy trust into the proper operation of the app.

If you read the reviews in Google Play Store, it is quite obvious, that many people are very confused about having 'Risiko-Ermittlung aktiviert", but if risk assessment fails, a button "Risiko-Ermittlung einschalten" is presented to the user.

To sum up, what @Jo-Achim and @MikeMcC399 already pointed out perfectly: This issue here is indeed two seperate issues, deserving 2 seperate Jira tickets.

1) The mainView/risk card is not completely refreshed, when

• the automatic background update has not been carried out for the current day, and
• CWA is openend by the user, and
• the diagnostic keys are exchanged in the background at the same time.

In this case @Jo-Achim can see the message "Risiko-Ermittlung nicht möglich, Risiko-Ermittlung einschalten", even the update succeeded. In my case, I see a green risk card, showing last update was done yesterday.
When you then navigate to a different screen/view, no matter whether inside or outside CWA, on return/onResume, the mainView is refreshed, and the correct status is displayed in the risk card.

Possible fix:

• Take care, that risk card shows "updating", when ProvideDiagnosisKeys is called during a foreground process.
• Make sure, that on receiving broadcast Action_Exposure_State_Updated app is in foreground, mainView is active, and refresh the view.
• If the above listener is not sufficient, additionally create a listener for Action_Exposure_Not_Found (as far as I could see from the code, no listener is set yet.) and refresh view on retrieval.

2) The much more severe problem imo, is, that a button "Risiko-Ermittlung einschalten" is displayed, even "Risiko-Ermittlung" is already active, up and running. This will not only happen, if there was no refresh (see 1), but also, if the automatic background update was not carried out for more than 24 hours. There are several reasons, why it was not carried out:
a) Telephone was shut down.
b) Battery optimization prevented the background task from being started.
c) Internet was closed.
d) Fetching diagnosis keys from server failed, and no re-try was set or could have been carried out.
e) The background update failed. It failed means, the background task was started, the diagnosis keys are fetched from the server, and ProvideDiagnosisKeys() is called, but ProvideDiagnosisKeys() fails. In the past, one reason was, that the counter for resetting the counter of API call rate limit was reset at local time in CWA, but in UTC time in ENF. That problem has been fixed. The much more severe current problem is, that ProvideDiagnosisKeys() may also fail, most likely because of internal timeout for an unknown reason (slow phone, too much file operation when shifting data from app to ENF when performing 14 single calls, concurrent processes, i.e. during reboot/start-up of the phone, etc...). Most of the people, who experienced API39508 will have had a problem with timeout in any way. While the hotfix in version 1.3.1 will take account of it, in the way, that ProvideDiagnosisKeys() won't be called again by CWA in the same day after a file batch has been sent, background updates may still fail.
As the number of diagnosis keys for matching are now rising for a considerable amount due to increasing infection rates, ENF will need to perform much more work in the next weeks. Hence, the likelihood for timeout problems inside ENF is rising. As the error message API39508 will not occur anymore, in cases of ENF timeout, people will then see more often that

• automatic update has not been carried out
• the message displayed on risk card will suggest them to activate "Risiko-Ermittlung" even it is/was already activated.

To cite @traut21 again:

The error warning is annoying and does destroy trust into the proper operation of the app.

Related to this is also: corona-warn-app/cwa-website#370

In my opinion, the flaws, that lead users to uninstall CWA should have highest priority in my personal opinion, but also as my opinion as health care researcher.
To hyperbolize a little:
Every installation of CWA has a small potential to save lifes by breaking infection chains.
Every uninstalltion of CWA has the potential to contribute to the death toll.

Maybe you can discuss with devs and POs, if this is worth to give higher priority.
Sorry for being a little bit polemic, but if you read the Google Play Store reviews in the last 3 months, it's sometimes hard to understand on which basis some decisions for further development of CWA are being made.

Thanks for your understanding!
❤️

Edit: I think the possible fix for 2) is clear, but consequences are more complicated. So, showing the button "Risiko-Ermittlung einschalten" should be dependent on status of exposure logging being enabled or not. If exposure logging is actually enabled, it's getting tricky - what to show then? First idea would be to create in-app information on what reasons might prevent the update from succeeding, giving some instructions to solve (if possible) or to link out to CWA-FAQ, and lead user to that information from that button. Button could display "Problembehebung" or "Details" or something similar.

[vaubaehn]

Hi @GPclips , see above,
... and welcome back! :)

[traut21]

There are several reasons, why it was not carried out:
a) Telephone was shut down.
b) Battery optimization prevented the background task from being started.

Concerning Battery optimization: From my radio app "VR" I know it will tell me that playback may be interrupted because of battery optimization. So there is a check for that kind of problem.

CWA never told me about potential problems because of battery optimization.

But maybe I did not get any warning because battery optimization had already been disabled.

For me it looks as if the app would not update properly if used within the background only. That's exactly what should have been fixed long ago.

[Jo-Achim]

Full agreement, @vaubaehn, especially ...

Every installation of CWA has a small potential to save lifes by breaking infection chains.
Every uninstalltion of CWA has the potential to contribute to the death toll.

I would add ...
In addition to the health issues mentioned, we should also consider the enormous financial and economic effort that will be required to deal with the pandemic.

[svengabr]

Hello everyone,

my original statement was that the 31508 errors are addressed in the upcoming hotfix release 1.3.1 however I agree with @vaubaehn that it makes sense to create two separate Jira tickets for the development team in order to counter the problems described here: #1081 (comment)

Thank you very much for your detailed feedback!

Best regards,
SG

Corona-Warn-App Open Source Team

[svengabr]

The mainView/risk card is not completely refreshed
Internal Tracking ID: EXPOSUREAPP-2795

"Risiko-Ermittlung einschalten" is displayed, even "Risiko-Ermittlung" is already active
Internal Tracking ID: EXPOSUREAPP-2796

[bufemc]

I have to stress this again:

The error warning is annoying and does destroy trust into the proper operation of the app.

I always have to struggle with this message, day for day, again and again, and for "normal human beings" (so, not "nerds") they will think the app stopped to work and will uninstall it. The app should be developed by putting yourself in the place of a normal person, not a nerd. It would be better to - at least - give the user "the feeling" that the app "still works". I would give the tickets a priority of urgent/high ,-)

[traut21]

It's not only the error warning.

Even if working properly, it does not update its value immediately, but does show the current update only after I take the next step to follow the (still) green "Niedriges Risiko" button area.

BTW, why doesn't the app tell me about the number of verfications? I can see that number via preferences > Google > "COVID-19 Benachrichtigungen": "Überprüfung auf mögliche Begegnungen". So it's no secret, although the App does hide that info.

[daimpi]

BTW, why doesn't the app tell me about the number of verfications? I can see that number via preferences > Google > "COVID-19 Benachrichtigungen": "Überprüfung auf mögliche Begegnungen". So it's no secret, although the App does hide that info.

Are you referring to this number?

What do you think would be the benefits of showing this number in CWA?

Also: the number which is currently shown there is too high: #1020

[traut21]

Yes, that's the number.

The benefit of this number would be to increase my trust in the proper operation of the CWA - that's why I asked within this topic. The current "Risk Determination not possible", the currently shown date of its last data update, all of this does increase doubt instead of trust in the proper behavior of the app.

[Jo-Achim]

I'm not sure, but there is something about the argument that cannot be dismissed out of hand. Because it shows the user that the CWA 'actually did something and that there were corresponding checks'!

(Please occasionally - as already said - accept the user's point of view, because they should use the app and trust it.)

[daimpi]

@traut21

Yes, that's the number.

The benefit of this number would be to increase my trust in the proper operation of the CWA - that's why I asked within this topic. The current "Risk Determination not possible", the currently shown date of its last data update, all of this does increase doubt instead of trust in the proper behavior of the app.

hmm… maybe you could open a separate issue in the wishlist repo for this enhancement request?

[traut21]

svengabr wrote three weeks ago about a fix "the next days".

Are the 43 000 000 €, which the Telekom received for service and maintenance, used up already?
I did not see any update or fix since.

CWA started poorly, got some fixes pretty soon, but now is in stagnation again. CWA, the next software BER?

[Jo-Achim]

@daimpi, referring to the above post #1081 (comment) maybe another hint.
Today after the first call of the CWA (v 1.5.0) "Updated: Yesterday ..." was displayed again. When I wanted to take a screenshot, I pressed the on / off / lock button too briefly ...
After switching on again, "Updated: Today 08:23" was correctly displayed in the CWA (start screen). Interestingly, under "Covid-19 notification", the time of today's review is given as 08:24.

Best regards.

[daimpi]

@Jo-Achim thanks for the update 🙂

I think what you were observing is: #948

I don't necessarily think there is a connection with this issue here… Imho it's more likely that it's just a rounding error of the timestamp.

[traut21]

I'm very sorry to report that the error has not been fixed

I had WLAN most of the time every day, but the CWA failed to look for updates for several days.

[daimpi]

@traut21 are we "just" dealing with the displaying problem in your case?

The mainView/risk card is not completely refreshed (EXPOSUREAPP-2795)

Or did CWA actually not perform any updates even when you opened it manually?

[Jo-Achim]

@traut21, allow me a little comment.
I usually only use WiFi for data exchange. If the cost aspect should play a role for you in this regard, see CWA FAQs: "When I'm not connected to a Wi-Fi network, will I be charged for any mobile data transmitted via the app?" / "Wenn ich die App außerhalb eines WLANs nutze, kommen dann Kosten für die Übertragung mobiler Daten auf mich zu?".
Maybe it's a workaround for you !?

[traut21]

@traut21 are we "just" dealing with the displaying problem in your case?

The mainView/risk card is not completely refreshed (EXPOSUREAPP-2795)

Or did CWA actually not perform any updates even when you opened it manually?

when I open it manually, it does show that it updated. But the message tells me that it did never do the update in the background since the last time I had opened it.

So the risk determination still does not work as needed.

[traut21]

@traut21, allow me a little comment.
I usually only use WiFi for data exchange. If the cost aspect should play a role for you in this regard, see CWA FAQs: "When I'm not connected to a Wi-Fi network, will I be charged for any mobile data transmitted via the app?" / "Wenn ich die App außerhalb eines WLANs nutze, kommen dann Kosten für die Übertragung mobiler Daten auf mich zu?".
Maybe it's a workaround for you !?

I don't think so. I do have both WLAN and mobile data turned on. But the CWA failed to obtain any updates.

[daimpi]

@traut21

I don't think so. I do have both WLAN and mobile data turned on. But the CWA failed to obtain any updates.

Do I understand you correctly that this is not just a displaying error? It persists even when you close and re-open CWA?

Some more questions:

• do you observe any other Error messages
• could you share your EN log
• which device do you use with which Android version?
• which CWA version are you running?
• which ENF version are you running?

[traut21]

If it tells me that the last update was on 2020-10-21, I have no doubt about that. But this means that it did not do any update since I did it last time, manually.
The status Risk determination not possible then is shown automatically, after about more than 48 hours since the last update?

I don't know about the close and re-open because I now had performed a manual update.

If the CWA does work with manual updates only, that's not what I need.

• no error messages
• where do I find the EN log?
• Android 10 on a Redmi 9
• CWA 1.5.0
• ENF 17203915000

[daimpi]

@traut21 thanks for the info 🙂.

I don't know about the close and re-open because I now had performed a manual update.

How do you perform a manual update? What steps do you take besides opening CWA if any?

where do I find the EN log?

On your phone's main screen: settings -> Google -> COVID-19 exposure notifications
click on the field where it says "checks performed in the last 14 days", this will bring you to a long list. You can export this list by clicking on the burger menu in the top right corner of the screen and select export.
To share the file here on GH just rename the file-ending from .json to .txt.

[traut21]

@traut21 thanks for the info 🙂.

I don't know about the close and re-open because I now had performed a manual update.

How do you perform a manual update? What steps do you take besides opening CWA if any?

I do click on the usally green, this time white area.

where do I find the EN log?

On your phone's main screen: settings -> Google -> COVID-19 exposure notifications
click on the field where it says "checks performed in the last 14 days", this will bring you to a long list. You can export this list by clicking on the burger menu in the top right corner of the screen and select export.

ok, It does confirm no update between 25. and 21.10.

all-exposure-checks.txt

[daimpi]

@traut21 thanks 🙂.

I do click on the usally green, this time white area.

I do think I know now what is happening: this seems to be a combination of issue #933 and

"Risiko-Ermittlung einschalten" is displayed, even "Risiko-Ermittlung" is already active
Internal Tracking ID: EXPOSUREAPP-2796

Do you have Prioritized Background Activity (PBA) enabled in the CWA settings? If so: could you leave a short comment over at #933 describing your situation?

Additionally you might find the following instructions helpful:

• https://www.coronawarn.app/en/faq/#no_risk_update
• https://dontkillmyapp.com/xiaomi

[traut21]

Do you have Prioritized Background Activity (PBA) enabled in the CWA settings? If so: could you leave a short comment over at #933 describing your situation?

PBA is enabled

Additionally you might find the following instructions helpful:

* https://www.coronawarn.app/en/faq/#no_risk_update

* https://dontkillmyapp.com/xiaomi

I expected that 1.5 should fix what has been reported in August here as a bug. Bummer, still not working...

My settings look different, but there are no battery savings restrictions for the cwa and background mobile data is enabled as well.

[traut21]

I'll need to watch it for some more time. But at the moment CWA 1.5.1 seems to update well within the background on my Redmi 9.

[traut21]

I'm sorry to report that the bug has not yet been fixed.

CWA today showed to me the common error message

which changed only after I went for a refresh

[d4rken]

Is this still an issue in 1.9.1+?

"Risiko Ermittlung einschalten"

There should be only 4 cards now.

• Increased risk (RED) <- Reflects last task result
• Low risk (GREEN) <- Reflects last task result
• Risk failed (WHITE) <- Reflects last task result
• Tracing off (WHITE) <- Reflects current device status

So if tracing is disabled, the "Tracing disabled" card with an "Enable tracing" button is shown, and in all other cases the card itself reflects the last result of the RiskLevelTask.
Which will cause it to either be red/green, or white if the task failed.

Timestamps

The "last updated" timestamp as of 1.9.1 is "the last time we submitted keys to the ENF":

cwa-app-android/Corona-Warn-App/src/main/java/de/rki/coronawarnapp/ui/tracing/card/TracingCardStateProvider.kt

Line 67 in 5bfc89c

lastExposureDetectionTime = latestSubmission?.startedAt,

while this may be off by a few minutes from what Google shows in the system's ENF, I don't have a better solution at the moment. I've tried "time when we submit to the ENF" and "time when the ENF tells us it's done calculating" and neither consistently matched the system's ENF timestamps.

[dsarkar]

Hi @traut21, @Jo-Achim, please see #1081 (comment).

Best wishes, DS

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Corona-Warn-App Open Source Team