Additional features, settings, or issues not covered by specific Microsoft Teams categories
First, on your Android device, just go to Setting >Accounts and Backup > Manage Accounts > and choose the Microsoft account you want to remove.
Then open your Microsoft account. From here you should work very fast. On the top left corner, select your Account Initials > setting > sign out of account (you may end up repeating this thing and pressing back to do this several times as Microsoft team want to login to your unwanted account)
Good luck!
Wooohoooo!
This worked!