Hello, I am the l Administrator of a Microsoft 365 tenant, but I am currently locked out because my Microsoft Authenticator app is no longer available. I cannot access the Admin Center or Azure Portal to reset my authentication methods.

Hello @Manuel Auer,

I'm very sorry for the inconvenience you’ve experienced, based on the details you shared.   

Could you please confirm whether the phone number you used to contact Microsoft Support matches the official Customer service phone numbers - Microsoft Support?

If the numbers match but you still experience issues when calling, you can try set up a new trial tenant and submit your support request:  

• Visit the Microsoft 365 Enterprise Plans page: Go to Compare Office 365 Enterprise Pricing and Plans | Microsoft 365.    
• Choose a plan and start a free trial: Select any of the available plans and click "Try for free" to begin the trial setup process.     

• Follow the guided setup: Complete the steps to create a new Microsoft account and a new tenant. This will be a separate and independent Microsoft 365 environment.    
• Access the Microsoft 365 Admin Center: Once the new tenant is created, navigate to https://admin.microsoft.com/.    
• After clicking on "Help & Support" button like this image, you can type "I need help". After that, you can click on "Contact support"   

• Choose contact method: "Phone" or "Email"   

Raise a support ticket: Describe your issue in detail. Crucially, you must clearly state that you are locked out of a different, pre-existing Microsoft 365 tenant where you are the only administrator. Provide the following information about your locked account:     

• Your administrator account email address for the locked tenant.    
• The domain name of your locked tenant     
• Any error messages you are receiving.    
• Details about the authentication issues you are experiencing.    
• Confirmation that you are the administrator of the locked tenant.    

Finally, clicking on "Contact me".   

Important notes:     

• This new trial tenant will not give you access to any of the data or settings in your original locked tenant. It is solely a temporary means to contact Microsoft support.    
• Be prepared for Microsoft support to ask for verification of your identity and administrative rights for the locked tenant.    
• The resolution time might be longer as you are contacting support from a different tenant.    
• Remember to cancel the trial subscription for the new tenant once your issue with the original account is resolved to avoid any unintended charges. You can typically do this within the Microsoft 365 Admin Center under "Billing" -> "Your products."    

Please understand that forum moderators have no control over user accounts, especially when it comes to logging in to your account, resetting your password, changing your access, etc.    

I hope Data Protection team can successfully revoke your access. If you need any further assistance or need help on any process, please feel free to reply. I'm here to help!   

Thank you for reaching out to us.

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