What is your account type? Personal account or work account.
Does the Teams web client have the same problem?
It seems that the error message is an Azure AD login error. It recommends you delete your Teams client cache as the following steps:
1.Fully exit the Microsoft Teams desktop client. To do this, either right click Teams from the Icon Tray and select ‘Quit’. Or run Task Manager and fully kill the process.
2.Go to File Explorer, and type in %appdata%\Microsoft\teams.
3.Once in the directory, delete any file in the following folders:
If it is no luck after that, you could uninstall and reinstall the Microsoft Teams client and have a try.
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