Hi @Dirk Townsend ,
Does this issue persist all the time?
Does anyone else have the same issue in your organization?
Do you mean you cannot login in Teams client normally is using old password?
Can you login in Teams web client normally?
In this case, we recommend you try to reset your password and then login it again to see if to works. For more details about how to reset password, you can learn it from:
https://support.teamapp.com/en/docs/64-reset-my-password
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