If you would share your version of thunderbird, your error messages and your server authentication, someone may have suggestions.

Do these instructions refer to your setup?

https://blog.thunderbird.net/2023/01/important-message-for-microsoft-office-365-enterprise-users/

A solution to the authentication issue will ship with version 102.7.1

That isn't correct anymore. There is only a release candidate for 102.7.1, which never made it to release status.

The current release version is 102.7.0, but this is broken as well. So your best bet is to downgrade to 102.6.1 for the time being, or wait until an official 102.7.1 version with a fix will be released, possibly in about a week.