Thanks for reaching out.
Earlier, we were allowing the establishment of additional free Microsoft Entra trial tenants using an existing free Microsoft Entra trial tenant.
However, our security team recently identified this practice for fraudulent and abusive activities.
In order to enhance your organization's security, Microsoft is now limiting this functionality to only paid customers. Customers on trial subscriptions will not be able to create additional tenants from the Microsoft Entra admin center. Customers in this situation who need a new trial tenant can sign up for a Free Azure Account.
Our product team is currently in the process of implementing additional modifications, and we will make the public document available once these changes are in effect.
Hope this will help.
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