Have you tried the way explains in the following article
I can't sign in to my Microsoft account
--please don't forget to upvote
and Accept as answer
if the reply is helpful--
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My Azure administrator account only has authenticator one verification method, I have got a new phone, and authenticator on the new phone doesn't add my Azure administrator account, so I can't log in.
Have you tried the way explains in the following article
I can't sign in to my Microsoft account
--please don't forget to upvote
and Accept as answer
if the reply is helpful--
Thank you for posting your question in Micrisoft Q&A.
As per your query you are having issues while logging in to Azure portal with administrator account.
You have registered for MFA in another phone. Now you are trying to register on a new phone and you are getting an error.
This is a normal behavior. Getting MFA registered in multiple phones creates security issues.
To fix your issue, you will have to contact another tenant administrator and get your MFA registration revoked.
To do this you can follow below steps,
Post this when you try to login to portal it will ask you to re-register for MFA. You can now register your MFA using new phone.
If you are the only global admin on the account and are blocked entirely, you can reach out to the Azure Data Protection team to restore access. 866-807-5850
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://docs.microsoft.com/en-us/azure/active-directory/roles/security-emergency-access
Some other support option include;
azcommunity@microsoft.com
or creating a ticket through a different account: https://learn.microsoft.com/en-us/microsoft-365/admin/get-help-support?view=o365-worldwide#phone-support
Let me know if you have any further questions.
Please "Accept the answer" if the information helped you. This will help us and others in the community as well.