update readme regarding the pre delete (#250)

* update readme regarding the pre delete


---------

Co-authored-by: Daniel Korac <99260961+danielforsap@users.noreply.github.com>

README.md

@@ -27,6 +27,7 @@ The SAP BTP service operator is based on the [Kubernetes Operator pattern](https
 * [Credentials Rotation](#credentials-rotation)
 * [Multitenancy](#multitenancy)
 * [Troubleshooting and Support](#troubleshooting-and-support)
+* [Uninstalling the Operator](#uninstalling-the-operator)
 
 ## Architecture
 SAP BTP service operator communicates with [Service Manager](https://help.sap.com/viewer/09cc82baadc542a688176dce601398de/Cloud/en-US/3a27b85a47fc4dff99184dd5bf181e14.html) that uses the [Open service broker API](https://github.com/openservicebrokerapi/servicebroker) to communicate with service brokers, acting as an intermediary for the Kubernetes API Server to negotiate the initial provisioning and retrieve the credentials necessary for the application to use a managed service.<br><br>
@@ -510,6 +511,61 @@ data:
 You're welcome to raise issues related to feature requests, bugs, or give us general feedback on this project's GitHub Issues page. 
 The SAP BTP service operator project maintainers will respond to the best of their abilities. 
 
+[Back to top](#sap-business-technology-platform-sap-btp-service-operator-for-kubernetes)
+
+## Uninstalling the Operator
+
+Before you uninstall the operator, we recommend you manually delete all associated service instances and bindings. This way, you'll ensure all data stored with service instances and bindings are properly taken care of. Instances and bindings that were not manually deleted will be automatically deleted once you start the uninstallation process.
+
+To uninstall the operator, run the following command:
+`helm uninstall <release name> -n <name space>`
+
+Example: 
+
+ >   ```
+  >   helm uninstall sap-btp-operator -n sap-btp-operator
+
+#### Responses
+
+   - `release <release name> uninstalled` - The operator has been successfully uninstalled
+
+   - `Timed out waiting for condition` 
+
+      - What happened?
+
+        The deletion of instances and bindings takes more than 5 minutes, this happens when there is a large number of instances and bindings.
+
+      - What to do:
+
+        Wait for the job to finish and re-trigger the uninstall process.
+        To check the job status, run `kubectl get jobs --namespace=<name space>` or log on to the cluster and check the job log.
+        Note that you may have to repeat this step several times untill the un-install process has been successfully completed.
+
+
+   - `job failed: BackoffLimitExceeded`
+
+     -  What happened?
+
+        One of the service instances or bindings could not be deleted.
+
+      - What to do:
+
+        First find the service instance or binding in question and fix it, then re-trigger the uninstalation. 
+
+        To find it, log on to the cluster and check the pre-delete job, or check the logs by running the following two commands:
+
+          - `kubectl get pods --all-namespaces| grep pre-delete`  - which gives you the list of all namespaces and jobs
+          - `kubectl logs <job_name> --namespace=<name_space_name>` - where you specify the desired job and namespace
+
+        Note that the pre-delete job is only visible for approximately one minute after the job execution is completed. 
+  
+        If you don't have an access to the pre-delete job, use kubectl to view details about the failed resource and check its status by running:
+
+          - `kubectl describe <resource_type> <resource_name>` 
+
+        Check for resources with the deletion timestamp to determine if it tried to be deleted. 
+
+
 ## Contributions
 We currently do not accept community contributions.