How to Deactivate and Reconnect your Microsoft 365 email account
If you are experiencing any errors or connection issues, you can check to see whether your email account is still connected by following the video below and you will come to a section where you will see whether your email account is connected or not connected (see image below video) and if it is not connected, carry on following the instructions in the video to disconnect and reconnect.
However, the cause of connection issues to third party services may be a number of reasons, and it would depend on the error message you are getting (if any).