Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello Fab
If your account belongs to an organization (company), you no longer have access to your old phone, and you cannot use any other verification method (such as a phone call, SMS, or email) to sign in, you will need to contact your IT Administrator or Global Administrator. They are the only people who can reset or update your authentication methods so that you can regain access to your account.
Manage user authentication methods for Microsoft Entra multi-factor authentication
- Sign in to Microsoft Entra - Microsoft Entra admin center
- User -> all users. Select the user you want to act on, and then select "Authentication methods". then select "Require multi-factor authentication re-registration".
Require re-enrollment MFA: This disables all previous authentication methods. You'll then be prompted to set up a new MFA authentication method the next time you try to sign in, so you can add a new authenticator app.
*Note:
- Please note that in this case, you only need to find the global admin of your organization’s tenant. They are the ones who can help you regain access to your account.
- The global admin is usually someone in your school’s IT team or a system administrator. They manage Microsoft 365 settings, licenses, and security.
I hope I’ve been able to help in some way. I look forward to your update.
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Take care, and have a great day!