Hi Voice Labs,
Thanks for reaching out to Microsoft Q&A.
As per the previous references to this issue raised by other users, please follow below details
Reference Link- https://answers.microsoft.com/en-us/msoffice/forum/all/problem-with-deleting-a-tenant-delete-all-license/d2cdc75c-52b1-4aad-a705-e7244b197041
If you have already deleted all license-based subscriptions, this should affect or deprovisioned after 72 hours,
If that is not the case, you can raise a support request to the Azure commerce team to check if there are any underlying subscriptions that are preventing the tenant deletion. As an organization admin, you can raise a service request to report this symptom to our online channel through the O365 admin center or the Azure Portal if you have the permissions. A support agent can further connect with you remotely, for further troubleshooting and involve the backend team where need be.
How to create an Azure support request - Azure supportability | Microsoft Learn
Get support for Microsoft 365 for business -- Online support.
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