If you have an issue with Teams going back to the sign in page after inputting email address (won't log in).
If it is a mobile device remove the Teams app & then reinstall.
If it is a windows PC or laptop remove temporary/cache files from Teams as follows:
- Quit Microsoft Teams (click on up arrow on task bar then right click on Teams & quit)
- Cut and paste the following location into File Explorer: %appdata%\Microsoft\Teams
- Delete contents of the entire folder
- Download & reinstall teams from teams.microsoft.com/download