Hi @為翰 黃
Could you please tell me if you have just encountered this problem recently, are you having this problem with the client, have you tried using the web version to see if this problem also occurs?
1.Clear Teams cache: If you are having a login problem with the client, if it is on the web version, please clear the browser's cookie cache.
2.Access Microsoft Teams from the web: If you are using the client, try using the Microsoft Teams web version. You can access the service from Google Chrome or Microsoft Edge.
3.Change the time zone: An incorrect time zone on your Windows PC may cause Teams login issues. Go to Settings > Time & Language > Date & Time > Expand the time zone and select the relevant option > Restart your PC and try to log in to your Teams account.
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