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I understand that you have lost your phone and that is the only device you have the authenticator app.
If you are using the work or school account, I suggest you reach the IT department of your school or office where they can help you to reset the MFA and re-register.
If you are the admin of your tenant, you can ask co-admin to reset your MFA.
If you have one account with admin role and if you 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#phone-support
Create 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 Entra ID. This account will help prevent being accidentally locked out of your Entra ID 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
Hope this helps. Do let us know if you any further queries by responding in the comments section.
Thanks,
Akhilesh.
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