Hello Saksiri Lertnilkarn,
Thank you for posting your query on Microsoft Q&A.
Vasil Michev has provided the answer, in addition to that I am proposing some more solutions to you for more better understanding.
Based on your description You got a new phone, installed the Microsoft Authenticator app, but now it doesn’t show the usual pop-up asking you to approve login attempts. It’s like the app forgot who you are or isn’t listening for the login request anymore.
You can Try Using the Verification Code to authenticate:
- Open the Authenticator app.
- Tap your account and use the 6-digit code instead of waiting for a push.
- This works even if push notifications fail.
You can Re-register the App
- Go to https://aka.ms/mysecurityinfo.
- Sign in using any available method (SMS, backup code, etc.).
- Click Add sign-in method → Microsoft Authenticator.
- Scan the QR code with the app.
- Set Authenticator code as the default method.
Fix Push Notification Issues
- Ensure notifications are enabled:
- iOS: Settings → Notifications → Authenticator → Allow.
- Android: App Info → Notifications → Allow.
- Disable battery optimization and allow background refresh.
- Ensure automatic date/time and network access without SSL inspection.
If you had cloud backup enabled, you could restore your accounts in the Authenticator app. Launch the app, and tap "Begin Recovery." Just make sure that you're logged in with the same Microsoft account you used for backup.
If you didn’t back it up, or can't access the old phone, you'll need to reset your MFA settings.
You're admin you can enabled, it with Self-service password reset (SSPR):
Go to https://aka.ms/mfasetup
Sign in and choose an alternate method (SMS/email)
Reconfigure your MFA device
You're not the only admin, ask another Azure AD admin to reset your MFA settings:
- Admin opens Microsoft Entra portal > Users > Select your account > Authentication methods> Click Require re-register MFA
In the case when you're locked out and no admin can help, contact Microsoft Support for identity to reset your MFA methods and Issue a Temporary Access Pass (TAP) for re-registration.
Reference for more understanding.
Microsoft support: https://support.microsoft.com/en-us/contactus?utm_source=chatgpt.com
Reset MFA via Admin: https://learn.microsoft.com/en-us/entra/fundamentals/
I hope this above information provided is helpful. Please feel free to reach out if you have any further questions.
If the answer is helpful, please click "Accept Answer" and kindly upvote it.
Regards,
Monalisha