Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
I understand how concerning this situation must be. If there are no accessible Global Administrator accounts in your tenant, you will need to contact Microsoft Support through one of the following options:
1.Contact Microsoft Support by phone: Customer service phone numbers - Microsoft Support
Since you mentioned that you've already contacted Microsoft Support by phone, may I ask whether you were able to get past the automated AI system and speak with a live support representative?
If not, and you're willing to try calling again, you may find the example below helpful, as it was shared by another user who was able to reach a live support representative in a similar situation.
Q. Can you tell me if you are calling as a home user who uses a product or service at home or a business user who uses it in your business to provide the best assistance?
A.I am a business user.
Q. Thank you. Can you give me the details of your inquiry?
A. Login technical support.
Q. First of all, can you tell me which products you are inquiring about today?
A. Microsoft 365 business Standard。
Q. Please wait a moment, I understand Microsoft 365. Are you calling about a new case or an existing one?
A. New.
Q. To receive phone support, your phone number must be associated with your Microsoft 365 admin profile. To do this, go to aka.ms/m365profile. Again, it aka.ms/m365profile . This can take 48 hours. In the meantime, you can go to aka.ms/m365profile and file a case online. If you prefer, you can also text the link to the phone number you are calling. What do you think?
A. The phone number is already linked to the link.
Q. Can you tell me about the products in your inquiry?
A. Microsoft 365 Business Standard.
Q. Are you a Global Administrator?
A. That's right.
Q. I'm sorry. I didn't understand. Are you a global administrator for your domain?
A. Yes, I am a global administrator for the domain.
Q. If you have any inquiries, you can contact a Microsoft representative. Are you sure?
A. Yes. Please.
Q. Yes, I understand. Please wait a moment.
Once connected, please explain that you need tenant ownership verification and Global Administrator recovery because there are no accessible Global Administrator accounts in your tenant. The support agent will be able to create a support case for your affected tenant and transfer it to the Data Protection team, who can assist with verifying ownership and restoring Global Administrator access.
Please note that this team is always overwhelmed, so you might need to wait for them to call you, this should take 3-10 working days. I know that this is not a convenient solution to hear but it seems to be the only way, and it's recommended that you should have a secondary/backup Global Administrator to fix this issue on your own.
2.If you are unable to reach the appropriate support team by phone, you can consider directly submitting a support request as a helpful workaround:
-Create a temporary Microsoft 365 tenant using a trial license: Go to Microsoft 365 Business Plans and Pricing and click Try for free to set up a temporary Microsoft 365 tenant with a trial license.
-Use this new account to sign in to the Microsoft 365 Admin Center and submit a support request on behalf of your primary (locked) account.
Note: This method doesn't require you to use the new account for your business. Instead, it allows you to create a temporary Global Administrator account so you can submit a support request for your affected tenant, where there are currently no accessible Global Administrator accounts. The trial account is free for one month. Be sure to delete it after submitting your support request to avoid any automatic renewals or charges from Microsoft.
For further instructions, you can follow this guide: Get support - Microsoft 365 admin | Microsoft Learn.
During the support process, Microsoft Support may ask for information to help verify ownership of the tenant and subscription, such as your company name, subscription details, billing information, proof of purchase, domain ownership, or other account-related information.
I hope this information helps.
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