Domain Addition - M365 Admin Center

Question

Hi Everyone,

I have added my organization's domain which was bought recently from Microsoft (No other outside vendor just a direct buyout) and I am trying to add a new domain which was added in my Amazon Route 53 and have given the necessary records in it. But I have been getting the error in the below frequently when I try to verify it.

"We have confirmed that you own xxx.co.uk, but we can't add it to your account because the domain is already added to a different Microsoft 365 organization: xxx.onmicrosoft.com. Sign in to the admin center as an admin for that organization, and remove the domain xxx.co.uk. Try resetting the admin password if you can't sign in. You should be able to add the domain xxx.co.uk here after taking that step. If you can't access xxx.onmicrosoft.com, please contact our support team for help."

Domain: xxx.co.uk Steps I have tried so far:

1. Tried removing the domain and adding it again.
2. Tried connecting with the error shown for other domain with multiple variants for helpdesk and tried with CTO's name as well but it throws an error domain does not exist.
3. Tried contacting support but they are asking for either Access ID or Contact ID ( But we don't have vendors we just bought it directly from Microsoft from UK site).
4. Tried to find the email to raise a ticket but it keeps getting back to my M365 admin center account or shows how to add the domain knowledge base.

Can I get help on this since it is URGENT from my side to add this domain and open shop.

Answer 1

Hi @Tech_Support_33 

Thank you for posting your question in the Microsoft Q&A forum.   

According to your issue, I understand that you have considered to add the domain that was previously configured in an old tenant. We are glad to assist you this part  

If you need to remove the old domain from the previous tenant before adding it to the new one, I recommend raising a ticket with Microsoft support. This will ensure you get the necessary assistance to resolve the issue effectively Get support - Microsoft 365 admin | Microsoft Learn 

You can also contact us via our phone service number: Customer service phone numbers - Microsoft Support. The agent will be able to create a ticket for you under the affected tenant and then transfer this ticket to Data Protection team who could help you.    

As forum moderators, we don’t have access to the detailed system needed to troubleshoot this effectively due to privacy and security constraints. We recommend contacting Microsoft’s support team directly, as they are best equipped to address and resolve this type of issue efficiently. 

Note: Please prepare any information related to the old tenant ( Access ID or Contact ID of Amazon Route 53) to prove your ownership. This will help the Microsoft team troubleshoot more effectively.  

If you can sign in to the Amazon Route 53 tenant, you can follow this article: Remove a domain - Microsoft 365 admin | Microsoft Learn to remove the domain from the previous organization and then add it to the new one. However, I strongly recommend raising a support ticket with Microsoft to ensure you receive the most accurate guidance and to help protect your important data during the process. 

If you need further assistance, please let us know.  

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Answer 2

Hi Tech_Support_33, That is called an unmanaged tenant. Here is a link to resolve your issue: https://learn.microsoft.com/en-us/entra/identity/users/domains-admin-takeover