You just changed your password and now the MS Teams app won't work on your desktop pc. You've tried to sign out and even rebooted with no success. Even your app on your mobile devices seems to work ok.
How to Fix:
1. Close MS Teams.
2. Click on the Start button and type Manage Your Account and click to select from the list.
3. You will then see an option to Fix Account. Click on this and it will then present you with a window to put in your new password.
4. Re-launch the Team app by clicking on Start and typing Teams, click to select from the list.