Microsoft and Google are working on a resolution. The immediate fix for Android 10 (and newer) devices if you use Microsoft Teams while signed out is to uninstall and then reinstall: If you have the Microsoft Teams app downloaded, but are not signed in, uninstall and reinstall the app. While this will address the problem in the interim, a Microsoft Teams app update is still required to fully resolve the issue. A coming Microsoft app update will more permanently fix the issue, with Google reiterating that those signed in to Teams are not impacted. Meanwhile, there will be an “Android platform update to the Android ecosystem on January 4” (security patch) to provide a more definitive fix for this emergency calling bug. Google ends by saying.
Google this afternoon provided the results of its investigation and confirmed it was “able to reproduce the issue under a limited set of circumstances.” The company is currently only aware of this one case brought to light on social media. Specifically, users might have an issue calling emergency services if they have Microsoft Teams installed, but are not logged in to the app: We determined that the issue was being caused by unintended interaction between the Microsoft Teams app and the underlying Android operating system. Because this issue impacts emergency calling, both Google and Microsoft are heavily prioritizing the issue, and we expect a Microsoft Teams app update to be rolled out soon