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I'm sorry to hear that you're having trouble signing in to your Microsoft account due to the authenticator app.
In the Entra admin center, an administrator can set user accounts to require re-register of multi-factor authentication (MFA).
Please have your administrator in your company to follow the steps:
1.Sign in to the Microsoft Entra admin center as at least one Authentication Administrator.
2.User -> all user. Select the user you want to act on, and select Authentication methods. then select Require re-register of multi-factor authentication.
3.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 add a new authenticator app.
(Reference :Manage authentication methods for Microsoft Entra multi-factor authentication - Microsoft Entra ID … )
Note:
-If you’re an end-user, please coordinate with your organization's administrator to handle these steps.
-If you need help finding your admin, please see: How do I find my Microsoft 365 admin? - Microsoft Support
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