Microsoft teams business acount unable to log-in

Dear @DCTS For WCEIS T-11,

Thank you for reaching out to the Microsoft 365 Q&A forum community. I understand how critical access to your Microsoft Teams account is, and I’m here to help you resolve this issue. 

Your account is protected by Multi-Factor Authentication (MFA). If the registered phone number or authentication method is no longer accessible, you cannot complete the sign-in process. 

If you still have access to your previous phone, try opening the Authenticator app there. You may be able to retrieve a verification code or approve the sign-in request.     

Use an alternative verification method: select “I can’t use my Microsoft Authenticator app right now.” This may allow you to verify your identity via SMS or email, assuming those backup methods were previously set up.    

As a member of the community support team, I’m limited in my ability to access or make changes within your administrator account. For security and privacy reasons, only Microsoft’s dedicated support team has the necessary tools and authorization to assist with account-level issues such as resetting or troubleshooting deep within your account.  

Option 1:

If there is another global admin in your organization 

Ask the other admin to log in to the Microsoft Entra Admin Center and reset your MFA settings:  

• Go to Entra ID > Users > Select your account > Authentication methods. 
• Choose Require re-registration for MFA or update the phone number. 

If you are a user (not an Administrator) 

For security reasons, you cannot reset your own MFA. You must contact your company's IT support or Microsoft 365 administrator. 

• Request that they "Reset MFA" or "Require Re-register MFA" for your account. 
• In the Entra admin center, an administrator can set user accounts to require re-register of multi-factor authentication (MFA).   

If you need help finding your admin, please see: How do I find my Microsoft 365 admin? - Microsoft Support 

Official guide: Manage authentication methods for Microsoft Entra multifactor authentication - Microsoft Entra ID |… 

Option 2: If You are the only global admin 

This is considered a tenant lockout scenario. You need to contact Microsoft Support to verify your identity and regain access:  

• Call the appropriate number from Customer Service Phone Numbers. 
• When prompted, select options for Authenticator issue > Office 365 for business > Company account > Administrator > No other admins > Service request. 
• The Data Protection team will assist after verifying your ownership of the tenant (billing info, domain details, etc.).  

For details, please follow this thread with the same issue in the forum: I have a Micrsoft business account and I am the admin and the only user registered under this accou… 

Option 3: Alternative options 

• If your subscription was purchased through a Microsoft partner or reseller, contact them to open a support request on your behalf. 
• You can also create a temporary trial tenant to submit a support ticket if needed. 

I hope the above information is clear. Thank you for your understanding and cooperation. Please let me know how it goes after trying the steps above. I’m here to help further if needed.  

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