CANNOT LOG BACK INTO AUTHENTICATOR APP SINCE I GOT A NEW PHONE

1. Why this happens

When you set up Authenticator for a work or school account, that account is tied to your old phone’s secure key.

If that phone is lost, reset, or replaced before you re-register the app, Microsoft has no way to verify you — so every login request fails or loops back to “Approve sign-in request.”

This is not something you can fix from your new phone alone; you need a reset or temporary access issued by your organization’s administrator or by Microsoft support if you are the admin.

2. If this is a work or school account (Microsoft 365 / Entra ID)

You must contact your organization’s Microsoft 365 administrator or IT department.

They can reset your multi-factor authentication registration in a few clicks:

Admin steps:

1. Sign in at https://admin.microsoft.com.
2. Go to Users → Active users → [your name].
3. Select Authentication methods → Manage multifactor authentication.
4. Click Disable MFA (temporarily).
5. You will then be able to sign in without MFA and re-enroll your device.
6. Once re-enrolled, the admin can re-enable MFA.

If you are locked out of admin access yourself (single admin scenario), proceed to Step 4 below.

3. If this is a personal Microsoft account

Go to https://account.live.com/acsr

This is Microsoft’s account recovery form.

You will need:

The email address of the locked account

An alternate contact email

Any details Microsoft can use to verify ownership (recent subject lines, billing info, Xbox ID, etc.)

Microsoft will review and, after verification, remove the old MFA requirement so you can log back in.

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