Microsoft authenticator issue

Good day Harley, 

Please note that forum users do not have access to user account settings and therefore cannot assist with login issues, password resets, multi-factor authentication (MFA) issues or changes to access rights. 

Based on your description, your school account is still associated with your previous phone. When you try to sign in, the account asks for approval from Microsoft Authenticator, but Authenticator hasn't yet been set up on your new device, which creates the sign in loop. Reinstalling the app doesn't transfer your existing school account to the new device automatically. 

Since you are using a school email address, the MFA settings are managed by your school's IT department. For assistance with resetting or updating your MFA, you will need to contact them directly to resolve this and explain your situation. You can say: "I am stuck in a login loop between Teams and the Microsoft Authenticator app. I cannot get the code to sign in."    

Note: In case you do not know who is your IT admin, kindly refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support  

Specifically, ask them to “reset my MFA settings” or “allow me to re-register for MFA” on your school account. This is a standard request and your school’s IT team should be able to assist you with it. 

You can also share the steps in this Microsoft article for them so they can help reset your MFA settings for you Manage user authentication methods for Microsoft Entra multifactor authentication.  

Once your school's IT admin has reset your MFA, the next time you log in to your account, you will be guided through the process of setting up the Microsoft Authenticator app again from the beginning by scanning a QR code. This will break the loop and allow you to access your account normally.   

Additional information is available in the following resource: How to add your accounts to Microsoft Authenticator | Microsoft Support 

I wish I could help more directly, but as a fellow user in this community, providing these steps is the best support I can offer. I hope your admin can help you regain access to your school account soon. 

If you have any questions, please don’t hesitate to reach out at any time. 

Thank you for your patience and understanding. 

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