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 those customers who have paid Microsoft Entra P1/P2 license. Customers on trial license 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.
Hope this will help.
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