Authenticator not working - Please help

Because the phone was replaced and Authenticator was reinstalled, the existing MFA setup is still tied to the old device. That is why sign‑in keeps asking for approval in Authenticator, but Authenticator itself cannot be set up.

Use these steps depending on the type of account and access still available:

1. If there is another MFA method configured (phone/SMS/email)
   • On the sign‑in screen where it asks for approval in Authenticator, choose “I can’t use my Microsoft Authenticator app right now” or similar.
   • Select another verification method (text message, call, or email) if it is listed.
   • After signing in, go to the Security info / Additional security verification page and:
     • Remove the old phone/Authenticator entry.
     • Add the new phone number and/or re‑add Microsoft Authenticator on the new device.
   • For step‑by‑step instructions with a screen reader, see the “I have a new mobile phone and I want to add it to MFA” section.
2. If still signed in somewhere (e.g., on a PC or browser)
   • While already signed in, open the Security info page (for example via the account manager → View account → Update info).
   • Delete the old phone/Authenticator method.
   • Add a new sign‑in method (phone and/or Authenticator) and complete the setup on the new phone.
3. If this is a work/school account and no other MFA method works, and no other admin exists
   • This is a lockout scenario. The tenant’s Global Administrator (if it is someone else) must reset the MFA methods or require re‑registration for the user.
   • If the locked‑out user is the only admin on the tenant, the Microsoft Data Protection team must verify identity and reset access. This is done by calling Microsoft Support using the regional customer service phone number and asking for a ticket with the Data Protection team for admin MFA reset.
4. If this is a personal Microsoft account and no method works
   • Use the account recovery options presented on the sign‑in page (e.g., “I don’t have any of these”) and follow the recovery flow, or contact Microsoft Support from the consumer support channel for further identity verification.

If Authenticator itself shows specific error messages (for example, “Authentication did not complete” or push notifications not arriving), also verify:

• The app is updated to the latest version.
• Notifications are enabled for Authenticator.
• The device has working network connectivity and correct date/time.

Once access is restored via any method, immediately add at least one backup MFA method (phone/SMS or alternate email) so a future phone change does not cause another lockout.

References:

• Use a screen reader to set up and troubleshoot multifactor authentication
• Troubleshoot problems with Microsoft Authenticator
• I have a Micrsoft business account and I am the admin and the only user registered under this account. I can't log in because i have replaced my phone and the authenticator doesn't work. - Microsoft Q&A
• Cannot authenticate with E-mail when logging into Microsoft Authenticator(iOS). - Microsoft Q&A
• Having problems getting text codes to confirm my account - Microsoft Q&A
• I need to reset my mfa methods - Microsoft Q&A
• Requesting a Tenant Admin MFA Reset - Microsoft Q&A