Can't login to Azure.com because it only works with authenticator app on my old phone

Hello Bret May,

Based on your description, it appears that you are unable to log into the Azure Portal due to an incomplete MFA process.

To fix this issue, you need to reset MFA on affected user account by logging in with another global administrator account into that tenant.

Please share the following steps with another Global Administrator in the tenant to reset your MFA settings:

1. Sign in to the Microsoft Entra admin center as an Authentication Administrator (or higher).
2. Navigate to Identity > Users > All users.
3. Select the affected user, then choose Authentication methods.
4. At the top of the window, click on "Require re-register MFA".

After this is done, you should be able to sign in again and register a new MFA authentication method when prompted.

If you're the only Global Administrator in the tenant, this qualifies as a tenant lockout scenario. In that case, we’ll need to involve Microsoft’s Data Protection team through a support ticket to help restore access.

To assist you further and forward this to Microsoft’s Data Protection Team, we need some additional information. As this involves Personally Identifiable Information (PII), please share the following details with us via private message only (do not post publicly):

• Contact phone number (including country code)
• Contact Email address
• Email address (affected account)
• Country
• Time zone
• Tenant domain name (e.g., contoso.onmicrosoft.com or verified custom domain)
• Tenant ID
• Azure subscription ID or billing information associated with the tenant (this helps confirm ownership)
• Locale

Once we receive this information, we will forward it to Microsoft’s Data Protection Team for further assistance.