Unable to receive notifications for 2 factor authentication and also set up a passkey

Hi @Basirat Omodasola Adebisi,

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Regarding your issue, since this is a school‑managed account, it would be best to contact your school’s IT support and ask them to reset your Microsoft Authenticator / MFA settings in Microsoft Entra ID. Once that’s done, you should be able to re‑register Microsoft Authenticator on your current device and complete the sign‑in or passkey setup successfully.

They can follow these steps:   

1. Sign in to the entra.microsoft.com as at least Authentication Administrator.   
2. Select User -> All user.   Select the user (your account) to act on and select Authentication methods. then select Require re-register of multi-factor authentication.    

• Require re-register MFA: This disables all previous authentication methods. You'll then be prompted to configure a new MFA authentication method the next time you try to sign in, so you can set up from the start and add a new authenticator app.   

For more details, please refer to: Manage user authentication methods for Microsoft Entra multifactor authentication. 

Note: Once re-registration is triggered, all your existing MFA methods such as phone numbers, Authenticator app, or other verification options will be removed. You will need to set up new MFA methods during your next login. Please ensure you have access to a valid phone number or the Microsoft Authenticator app before attempting to sign in again. 

Hopefully it will help work with your issue and if you have any other questions or need further assistance, feel free to ask.   

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For the missing Microsoft Authenticator notifications and the passkey error, use the following steps.

1. Fix missing Authenticator notifications

• Make sure notifications are allowed for Microsoft Authenticator in the phone’s Settings (push notifications enabled, sound/vibrate allowed, not blocked).
• Confirm the phone is not in Do Not Disturb/Quiet mode.
• Check that other apps can receive notifications; if none can, there may be a network or OS notification-channel issue on the device.
• If some accounts in Authenticator get notifications but the school account does not, remove the school account from the app and add it again, allowing notifications during setup.
• If the app shows “Enable push notifications to receive alerts,” enable push notifications in device Settings and ensure the phone has network connectivity, then try adding the account again.

If there is an older phone where Authenticator was previously used:

• A push may be going to the old device instead of the new one. Open Authenticator on the old device (if available) and approve the sign-in, then follow the FAQ guidance to remove old devices so future pushes go only to the current phone.

2. If sign-in is blocked after multiple attempts If there have been many failed sign-in attempts while testing:

• Microsoft Entra multifactor authentication can temporarily block further attempts. Wait and try again later, or use a different MFA method (for example, SMS or email, if your school has enabled them).
• If there is any suspicion that someone else is trying to access the account, contact the school’s IT administrator and ask them to check Microsoft Entra sign-in logs and MFA configuration.

3. Handling the passkey/MFA issue as a school (work/education) account Because this is a school account:

• Only the organization’s IT/Help desk can reset or clear MFA settings for the account.
• Contact the school’s Help desk/IT support and ask them to:
  • Clear existing MFA/Authenticator registrations for the account.
  • Enable re-registration so the account can be set up again on the reinstalled Authenticator app.
  • Verify that passkey and passwordless sign-in are allowed for the tenant and for this user.

If the mobile device was changed or reset:

• Inform the Help desk that the phone was reinstalled and that the Authenticator registration needs to be cleared. After they clear it, the next sign-in will prompt to register Authenticator and any passwordless/passkey methods again.

4. If verification codes are not received

• If SMS or email verification is configured but codes are not arriving, choose another available method or wait until the registered phone/email is accessible.
• Support agents cannot send verification codes or change account details directly; this must be handled by the school’s IT administrators.

5. Security note for unexpected codes If any verification codes arrive that were not requested:

• Do not respond to or approve them.
• The account remains safe as long as unrequested codes are not used.
• Consider asking IT to help move the account toward passwordless methods (Windows Hello, Authenticator, security key) for stronger protection.

Because the error code 500121 and the tenant’s exact configuration details are not exposed here, the key action is to work with the school’s IT/Help desk to reset MFA and confirm passkey support, then re-register Microsoft Authenticator on the current phone following their instructions.

References:

• Troubleshoot problems with Microsoft Authenticator
• Common problems with two-step verification for a work or school account
• Microsoft Authenticator FAQs