how to reset mf2 azure admin account after losing the phone

If you have other admins in the account, they can make you register the MFA.

Refer: https://video2.skills-academy.com/en-us/troubleshoot/azure/entra/entra-id/mfa/cannot-use-mfa-signin-lose-phone

If you have only one account and you lost the MFA, and if you enabled backup and recovery for your authenticator app, then can be restored to a new device.

Refer: https://support.microsoft.com/en-us/account-billing/back-up-account-credentials-in-microsoft-authenticator-bb939936-7a8d-4e88-bc43-49bc1a700a40

If the above also does not work, then create a support request.

https://ms.portal.azure.com/#blade/Microsoft_Azure_Support/HelpAndSupportBlade/overview?DMC=troubleshoot

Hi, Bassam Omar

I understand that your manager lost his device and can’t use authenticator app, so you need to reset MFA to re login to your subscription.

Reach out to the global admin in your tenant, you can contact them to re-register for MFA

1. Sign in to the Azure portal.
2. Navigate to Microsoft Entra Id > Users > All users.
3. Choose the user you wish to perform an action on.
4. Select Authentication methods.
5. Click "Require re-register MFA"
   

Then you can reset MFA and can access your authenticator app

For further reference: Manage authentication methods for Microsoft Entra multifactor authentication - Microsoft Entra ID | Microsoft Learn

Hope this helps. Do let us know if you have any further queries.

Thanks,
Prakash V.

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