@Victor Gonzalez
Thank you for posting this in Microsoft Q&A.
Earlier, we were allowing the establishment of additional free Microsoft Entra trial tenants using an existing Microsoft Entra 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.
Reference - https://learn.microsoft.com/en-us/entra/fundamentals/whats-new#general-availability---restrict-microsoft-entra-id-tenant-creation-to-only-paid-subscription
Let me know if you have any further questions on this.
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