new phone and my authenticator app isnt working

Hi Kathryn,

Thank you for your detailed sharing, and I'm sorry to hear you're having trouble logging into your Microsoft account.

This issue commonly occurs when your Multi-Factor Authentication (MFA) settings need to be reset. The app is still tied to your old phone, and the new one hasn’t been configured with the Authenticator yet, but since you have erased your old phone entirely, it leads to the situation that you're currently unable to access your account.

In this case, the most appropriate next step is to contact your school's Microsoft 365 administrator. You can share with them the steps outlined in the article Manage user authentication methods for Microsoft Entra multifactor authentication to revoke existing MFA sessions and require re-registration. This process usually only takes a couple of minutes.

Please note that this is a user-to-user support forum, and I do not have access to administrative tools or permissions to reset or modify MFA settings on your account. Because your account is managed by your school, only an authorized Microsoft 365 administrator at your institution can make these changes.  

Once finished, the next time you sign in, you will be prompted to set up Microsoft Authenticator again from the beginning, and verification codes should be delivered normally. If appropriate, you may also wish to ask the administrator to add an additional authentication method, such as SMS or email, to help ensure continued access in the future.

If you’re unsure who your Microsoft 365 administrator is, the following article can help you identify the correct contact at your school: How do I find my Microsoft 365 admin? - Microsoft Support.

I hope this information helps point you in the right direction and allows you to regain access to your account as quickly as possible.

Thank you for your cooperation and understanding.

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