Dear @Ariana Rodarte,
Good day! Welcome to Microsoft Q&A forum!
Based on your description, I understand that you deleted the Authenticator app linked to your school Microsoft account, reinstalled it, and are now unable to sign back in because the login process requires a verification code from the authenticator app, which itself is asking for a code to complete sign-in.
I sincerely apologize for the inconvenience caused by this issue.
Regarding this situation, this occurred because the Authenticator app was removed from your device, which also removed its trusted connection to your account. When you reinstalled it, Microsoft no longer recognized the app as verified, so it asks for confirmation again. Since the Authenticator itself was your verification method, it creates a loop.
If you're an end-user, please reach out to your IT administrator for assistance. If you’re unable to sign in due to a phone change, a new phone number, or issues receiving your authentication code, your IT administrator can help by updating your authentication methods or revoking and re-registering your authentication.
Please note that forum moderators have no control over user accounts, especially when it comes to logging in to your account, resetting your password, changing your access, etc.
For detailed guidance, kindly ask your IT administrator to review the step-by-step instructions provided in the referenced article: Manage user authentication methods for Microsoft Entra multifactor authentication
Here's how to find your IT Admin: How do I find my Microsoft 365 admin? (please also kindly reach out to your friends, professors, etc. to see if they have the IT department contact)
As much as I’d like to assist you directly, only your school/organization's IT administrator can reset or update the authentication settings for your account. Please reach out to them for further help, as they have the necessary access to resolve this issue.
Kindly let me know when there are updates or if you need further assistance. Any updates you’re able to share would be really helpful.
I'm here and happy to help! Thank you for your kindness and patience!
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