Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Dear Paula,
I'm sorry to hear you are locked out of your university account after changing phones. I can imagine how stressful this is when you need access for your studies. Unfortunately, as a forum moderator, I am not able to reset MFA methods or make changes to your account. My role here is limited to general guidance you can apply from your side.
This is a common situation after changing devices. At the sign-in prompt, first try selecting "I can't use the Microsoft Authenticator app right now". If you registered another method previously, such as a phone number, you can verify that way and set Authenticator up again on your new phone yourself.
If Authenticator is your only registered method, you will need your university IT help desk. Ask them to require you to re-register for MFA. That clears your old registration and prompts you to set up Authenticator on your new phone the next time you sign in. Using that wording should help them action it quickly. If you don't know who your IT administrator is, please refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support
I hope this information is helpful and provides you with a clear path forward. Should you have any further questions or need additional assistance, please don't hesitate to reach out. I'm always happy to help.
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