Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Dear @Imthrist D
Based on your description, I understand that you are using an education account. For work or school accounts, there is no self-service way to reset or remove Microsoft Authenticator if you cannot complete MFA and no alternative verification method is available.
In this case, since your school has an MFA setting for your account, I highly recommend you contact your school IT staff directly so that they may reset your MFA settings to your new mobile. You might also ask whether your MFA can be temporarily disabled to allow an emergency sign-in. For more information: How do I find my Microsoft 365 admin?
For that reason, only the school IT admin can revoke MFA sessions and require re-registration in the Microsoft Entra admin center
For more information and instructions, please ask the school IT Admin to follow the Microsoft Official Guide here: Manage authentication methods for Microsoft Entra multifactor authentication - Microsoft Entra ID | Microsoft Learn
I hope the information shared is helpful. If you have any questions, please feel free to reach out. I'm looking forward to your update.
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