Can't verify through authenticator app

Question

Error Code: 500121

Request Id: XXX-XXX-XXX-XXXX-XXXX

Correlation Id: XXX-XXX-XXX

Timestamp: 2025-06-19T07:43:49Z

Answer 1

Hi Mahiya Balaji

Thank you for posting your question in the Microsoft Q&A forum.    

Please understand that our forum is a public platform, and we will modify your question to cover your organization domain name in the description. Please notice to hide these personal or organization information next time you post error or some information to protect personal data. 

According to your issue, I understand you are unable to get the two-factor authentication (2FA) code when using the Microsoft Authenticator app (error code: 500121).  Here are a few suggestions that may help resolve the issue: 

If you are still signed in to Office 365 on a browser: 

1. Go to: https://mysignins.microsoft.com/security-info 
2. Sign in with your Office 365 account. 
3. Under Security Info, remove the Microsoft Authenticator method. 
4. Add a new sign-in method (e.g., phone number, email, or reconfigure the Authenticator app). 

If you are locked out and cannot sign in, since your account is part of an organization, please contact your company’s IT administrator to request a Multi-Factor Authentication (MFA) reset. They will be able to assist you in regaining access to your account. To help them proceed, kindly ask your IT administrator to follow the steps outlined in the following Microsoft Learn article: Manage authentication methods for Microsoft Entra multifactor authentication - Microsoft Entra ID | Microsoft Learn 

In case you are the only Global Administrator and you are completely locked out from the tenant. You might need to contact us via phone service number: Customer service phone numbers - Microsoft Support. The agent will be able to create a ticket for you under the affected tenant and then transfer this ticket to Data Protection team who could help you to regain access.   

For additional details, please refer to the following link Error 500121 when trying to use the Authenticator app - Microsoft Community 

We hope this helps resolve your issue. Please let us know if you need further assistance.  

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