Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
First, I'd like to mention that I'm an Independent Advisor, not a Microsoft employee. I'm here to help based on my experience with similar issues and hopefully point you toward the quickest resolution.
From what you've described, this does appear to be an MFA (multi-factor authentication) issue, where the Microsoft Authenticator app is not receiving the approval prompt or code needed to complete the sign-in process. This can unfortunately create a situation where you're unable to access either your account or the settings needed to fix the problem yourself.
In this situation, since you are using a college/school account, the best course of action is to contact your school's IT administrator. They have the necessary permissions to reset your multi-factor authentication settings and help restore access to your account.
You can ask them to follow the steps outlined in the following guide to revoke your existing MFA sessions and require MFA re-registration: Manage authentication methods for Microsoft Entra multifactor authentication - Microsoft Entra ID |…
This process typically takes only a few minutes. It clears the existing authentication registration and sign-in sessions, and the next time you sign in, you should be prompted to set up Microsoft Authenticator again from scratch on your phone.
As this is a user-to-user support forum, I can only provide guidance based on experience with similar cases and cannot make changes to your account directly. Because your account is managed by your educational institution, only your school's IT administrators have the authority to modify these security settings on your behalf.
That said, I sincerely hope this information helps point you to the right support team so that you can regain access to your account as quickly as possible and continue your studies without further interruption.
Thank you again for your time and understanding.
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