1.Please try uninstalling Teams and reinstalling it.
2.In Windows Settings > Accounts > Access work or school, delete the account and add it again, then sign in to check the results.
If the above method does not work, this may be due to a temporary issue with New Teams. You can contact the administrator to report the issue in the M365 admin center.
Tell MS about a new outage, slowdown, or other service issue you're experiencing. If confirmed, MS will add it to the Incidents list so you can track its progress and resolution.
Thank you for your understanding and support.
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