Authenticator

hi DadJo​  You’re unfortunately in a tough but fairly common situation losing access to the Authenticator app when you’re the only admin can lock you out completely.

A few things to try :

1) Check if you have any backup authentication methods

Try signing in and choose “I can’t use my Authenticator app right now”

See if options like:

Alternate phone number

Email

Backup codes (if you ever saved them) show up

Even if SMS/call isn’t working, double-check the number is correct in your account.

2) Try restoring the Authenticator app

If you previously enabled backup in Microsoft Authenticator:

Install it again on your new phone

Sign in with the same personal Microsoft account

Use the restore from backup option

This only works if backup was enabled earlier, but worth trying.

3) Use another Global Admin (if any exists)

If there’s any other admin account in your tenant, they can:

Reset your MFA

Remove/re-register your authentication methods

4) If you are the only admin (most likely case)

Then this becomes a tenant lockout scenario, and self-service recovery usually won’t work.

You’ll need to contact Microsoft support directly and request:

MFA reset / admin account recovery

Try this path:

Go to Microsoft 365 Admin support (even if you can’t sign in)

Use the “call support” / “conxxct us” option

Explain clearly: “Global admin locked out due to lost Authenticator device”

They may ask for:

Business verification (domain ownership, billing info, etc.)

Important note

Microsoft is intentionally strict here for security reasons, so the process can take a bit of time, but they can recover access after verification.

For future (once you’re back in):

Add a second admin account (very important)

Enable multiple MFA methods (phone + app)

Save backup/recovery codes

Enable Authenticator backup

You’re not alone this happens more often than you’d think. The key is getting Microsoft support involved for identity verification and an MFA reset.