Hi @Ryan Sur
Thank you for posting this in Microsoft Q&A.
I understand that you haven't logged into Microsoft Entra ID/Azure AD recently and you have switched phones, where the authenticator was configured for your tenant. Now, you are unable to log in because the MFA codes are not being sent to your new mobile phone.
The tenant account MFA is registered on your old phone, and you haven't configured MFA on your new phone or transferred it over. This causes the authentication codes to still be redirected to the old phone.
1.If you have any other MFA options enabled for your account, you can click "I can't use my authenticator app right now" (if you see any other available options) and use those methods. Once logged into the portal, you can configure Microsoft Authenticator again.
2.If there is another global administrator in your tenant, they can assist you with MFA recovery. Please contact them and request that they re-register MFA on your behalf. This action will remove existing MFA methods, including phone numbers, Microsoft Authenticator apps, and software OATH tokens. You will need to set up a new MFA authentication method the next time you sign in.
For your reference: https://learn.microsoft.com/en-us/entra/identity/authentication/howto-mfa-userdevicesettings#manage-user-authentication-options
3.If you are the only global admin on the account and are blocked entirely, you can reach out to our support team. You can look into below article to get support numbers depending on your country.
or creating a ticket through a different account: https://learn.microsoft.com/en-us/microsoft-365/admin/get-help-support?view=o365-worldwide#online-support
While creating a ticket with Microsoft support team. Give them the tenant ID which is locked out in your description. Tell them that no admin account has access anymore and your partners also have no access anymore.
Once you create a ticket with support team you will have to work with our data protection team. You will have to first prove your identity against your tenant for security purpose. Post that this team will help you with help you in getting access to your tenant or unlock your account depending on your scenario.
Also, for the future, you can create an emergency access account (break glass) in Azure AD. This account will help prevent being accidentally locked out of your Azure Active Directory (Azure AD) organization because you can't sign in for any reason.
https://learn.microsoft.com/en-us/entra/identity/role-based-access-control/security-emergency-access
Hope this helps. Do let us know if you any further queries.
Thanks,
Navya.
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