How to fix Error Code: 500121 for microsoft authenticator app.

Question

I am trying to log in to my school's learning hub, but I cannot do it without the app, however every time I send an authentication code to the app, it does not appear. I have tried all options referring to two factor authentication issue and they all refer back to the app, which isn't working.

It is sending me this error code,
Error Code: 500121

Request Id: [Moderator note: Personally Identifiable Information removed]

Correlation Id: [Moderator note: Personally Identifiable Information removed]

Timestamp: 2026-06-04T00:15:46Z

Is there any way you can please help me? I cannot log in to the connected accounts email address either.

Answer 1

Dear @LIAM CAHOON,

I understand how frustrating it is to be locked out of your school's learning hub and email, especially when the tool meant to help you login isn't delivering the codes.

Error Code 500121 indicates a Multi-Factor Authentication (MFA) timeout or configuration failure. It means the login portal is waiting for a response from your Microsoft Authenticator app, but the communication loop is broken, often caused by notification blocks, mismatched app states, or broken device registration.

Since you cannot access your account to change settings, please try these steps to resolve the issue:

Step 1: Force Sync & Check Notifications 

Often, the notification is blocked by your phone's background restrictions.

• On Android: Go to Settings > Apps > Authenticator > Battery > Set to Unrestricted. Then check Notifications and ensure all alerts are allowed.
• On iOS (iPhone): Go to Settings > Authenticator > Notifications > Turn on Allow Notifications.
• Manually Check: Open the Authenticator app, pull down on the screen to refresh/sync, or click on your school account inside the app to see if a one-time 6-digit passcode is cycling. If you see a cycling code, try clicking "Sign in another way" on your browser and select "Use a verification code" instead of a push notification.

Step 2: Clear Browser Conflict

Sometimes your browser sends outdated credential tokens that fail the MFA handshake.

• Open an Incognito or InPrivate browser window.
• Go directly to your school's learning hub portal and try logging in again.

If the steps above do not work, you will need to contact your school’s IT Department or Helpdesk. According to official Microsoft Entra ID security protocols, when an end-user is completely locked out of both their email and their Authenticator app, only an administrator can reset the authentication method. 

Because this is a security-level lockout, I cannot bypass this system for you from the forum, but your school's IT team can fix this for you in under two minutes using the step above.

Please have your administrator follow the steps shown in the following article: Manage authentication methods for Microsoft Entra multi-factor authentication - Microsoft Entra ID …

Please let me know if your school's IT team requires any further technical clarification to get you back into your account.

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