Dear @פיליפ ברוש - Philip Brosh,
Thank you for posting your question in the Microsoft Q&A forum.
Based on your inquiry, we understand that you have considered to add an old domain, which was previously deleted with your old business, to your new tenant. We will be glad to assist you in 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.
Noted: Please prepare any information related to the old tenant to prove your ownership. This will help the Microsoft team troubleshoot more effectively.
We hope this information is helpful and appreciate your understanding.
If you need further assistance, please let us know.
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