How do you reset Authenticator app on new phone - old phone is broken which had the Authenticator app on it- I can’t log in

Hello @Carla and @Dominic Corriveau,  

Thank you for posting your valuable question on Microsoft Q&A forum.   

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

Since you are the sole administrator in your organization, you must first work with the Microsoft Data Protection team to revoke your own admin access. Once that is completed, you can use the admin account to remove access for your users. Please try to find the related hotline number to call the frontline and let them raise a ticket for you: Customer service phone numbers - Microsoft Support 

Please carefully follow this instruction to ask for Microsoft Data Protection team support:   

Depending on your country or region. For some countries, when calling the support number, although there are about 30 seconds opening as something "you can visit the link...." But you can ignore this opening and wait until the option, then "1" as a business email user, "1" again for technical help.   

For some countries, it will be an automated conversation like:    

First, when you call the hotline, it asks what kind of problem you are worried about.   

Answered: authenticator.   

A: What kind of product are you using?   

B: Office 365 for business.   

A confirmation: education or company account?   

B: For companies   

A: Are you an administrator?   

B: Yes.   

A: Do you have the other admin in your organization?   

B: No.   

A: You need one.... Service request?   

B: Yes   

If your organization's Office 365 Business/Education subscription is from a partner or reseller, and the global administrator is unable to open a service request on your end, contact the reseller's support provider to help open a service request on behalf of you instead.   

Alternatively, 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/.   
• Go to Support:  
• 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 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."   

After gaining access to the admin account, follow these steps to revoke user account access:

• Go to Microsoft Entra Admin Center: https://entra.microsoft.com  
• Navigate to Users > All Users.  
• Select your user account.  
• Go to Authentication Methods.  
• Click "Require re-register multifactor authentication". 

This will reset your MFA settings. The next time you sign in, you’ll be prompted to set up the Authenticator app again using a QR code.  

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 your kindness and understanding so far! 

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