Contact your school’s IT help desk and ask them to require MFA re-registration for your student account, because the Authenticator registration for a work or school account cannot be transferred to the new phone without signing in again.
Regain access
- On the Microsoft sign-in page, select Sign in another way or Other ways to sign in, if displayed.
- Use another method only if one was previously registered, such as SMS, a phone call, security key, or passkey.
- If Authenticator is the only available method, contact your school’s IT help desk. Send them this request:
I replaced my phone and no longer have access to the Authenticator registration on my old device. Authenticator is my only verification method, so I am stuck in a sign-in loop. Please require MFA re-registration for my student account or provide an approved Temporary Access Pass so I can register Authenticator on my new phone.
This matches the supported recovery for a school account when the old Authenticator device is unavailable.^1^
What the school administrator needs to do
An Authentication Administrator can:
- Open Microsoft Entra admin center.
- Go to Entra ID → Users.
- Select your student account.
- Select Authentication methods → Require re-register MFA.
That action removes the existing phone numbers, Authenticator registrations, and software OATH tokens from the account. At your next sign-in, you will be prompted to register a new authentication method.^2^
Alternatively, if permitted by the school, the administrator can issue a Temporary Access Pass. You can then install Authenticator, select Add account → Work or school account → Sign in, and use that pass to register the new phone.^3^
Why restoring the app does not resolve the loop
Authenticator backup restores only the account name for work or school accounts—not its authentication credentials. The account must still be signed in and registered again on the new device.^4^
After access is restored, register an additional method allowed by your school so a future phone replacement does not leave Authenticator as the only available option.
References
- authenticator app issue after changing to a new phone - Microsoft Q&A
- Manage user authentication methods for Microsoft Entra multifactor authentication
- Enable passwordless sign-in with Authenticator
- [Android](https://support.microsoft.com/authenticator/restore-account-credentials-from-microsoft-authenticator#what-information-is-restored-in-authenticator)