hi Solbi,
are you getting the same issue when connecting to Teams via the web app using an in-private session with for example Edge?
you can also ask your Teams Admin to run a diagnostic:
- Run Tests: Teams Sign-in
- In the Username or Email Address field, enter the email address of the user who's experiencing the Teams sign-in issue.
for more information you can visit this link:
https://learn.microsoft.com/en-us/microsoftteams/troubleshoot/teams-sign-in/resolve-sign-in-errors
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