Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Dear 千晶(ちあき) 西岡(にしおか),
Thank you for posting your question in the Microsoft Q&A forum.
Regarding the issue where you are unable to complete the receive verification code for Administrator login, which results in the inability to reduce licenses. Please kindly check whether your tenant has another Global Administrator who may be able to assist you with this issue?
If other user still holds the Global Administrator role, please kindly follow these steps:
- Sign in to the Microsoft Entra Admin Center using an account that has at least the Authentication Administrator role.
- Navigate to Entra ID > Users.
- Select the user whose MFA authentication methods you wish to reset, then choose Authentication methods.
- Select Revoke multifactor authentication sessions, and then select Require re‑register multifactor authentication.
- After completing these steps, the user will need to set up MFA again. You can do this by signing in and configuring MFA through the Microsoft Authenticator app on mobile device.
If you are the only administrator in your organization, you will need to contact the Microsoft Data Protection team for further assistance. Please locate the appropriate support phone number for your country or region and contact Microsoft Support so the frontline team can raise a service request on your behalf: Customer service phone numbers
When calling the support number, the experience may vary depending on your country or region:
- In some regions, you may hear an automated message for approximately 30 seconds. You can ignore this message and wait for the prompt, then select “1” for Business email user and “1” again for Technical support.
- In other regions, you may be guided through an automated conversation similar to the following:
- The system asks what issue you are experiencing → Authenticator
- Product in use → Office 365 for Business
- Account type → Company account
- Administrator status → Yes
- Are there other administrators in the organization? → No
- Proceed to create a service request → Yes
If your Office 365 Business or Education subscription was purchased through a partner or reseller, and you are unable to open a service request directly, please contact your reseller’s support provider and ask them to raise the service request on your behalf.
Alternatively, if you are unable to reach support by phone, you may create a temporary trial tenant to submit a support request for the block access tenant through the Microsoft 365 admin center. You can start with a trial license here: Microsoft 365 Business Plans and Pricing | Microsoft 365
Important: Please remember to cancel the trial subscription after your original account issue is resolved to avoid any future charges.
Once you have successfully signed in to your account, please follow the steps outlined in the Microsoft documentation to cancel your subscription via the Microsoft Admin Center: Cancel your subscription in the Microsoft 365 admin center
Note: Please understand that as forum moderator, our primary goal is to provide helpful guidance and support through general troubleshooting steps. While we don’t have access to internal systems or test devices required to resolve backend/account issues, we truly appreciate your understanding of these limitations. we genuinely hope the information helps you in the right direction, and we are always here to assist as much as we can within our scope.
I hope the above methods will be able to assist you in restoring access.
Thank you for your patience and understanding. I hope the information above is helpful. If you have any further questions, please feel free to reach out.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.