Internal Server Error 500 After Recent .NET Runtime Upgrade

[shribr]

After recent updates to the repo (last week or so) I get an HTTP 500 error when trying to chat with the bot. I have two copies of the repo. The first is the new one (not the .NET runtime version is 8.0.8.9) and the second is the old one that works which has .NET runtime 8.0.7.1.

Solution Error with new .NET Runtime 8.0.8.9:

Solution No Error with old .NET Runtime 8.0.7.1:

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This issue is for a: (mark with an x)

- [ x] bug report -> please search issues before submitting
- [ ] feature request
- [ ] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)

Minimal steps to reproduce

Any log messages given by the failure

Expected/desired behavior

OS and Version?

Windows 7, 8 or 10. Linux (which distribution). macOS (Yosemite? El Capitan? Sierra?)

Versions

Mention any other details that might be useful

Here is the network traffic for both solutions when making the call to the api/chat endpoint:

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Thanks! We'll be in touch soon.

[shribr]

I didn't have search indexes defined in my Search Service. My bad.