If you have Orchestrator License then activate the Orchestrator license first then activate the UiPath Studio license and it is always recommended to contact the technical support team for Enterprise license issues.
@atoi Did you request a Studio Trial or an Enterprise Server Trial? They have different license models: Studio has a per user license model and Orchestrator has a server model. So you won’t be able to activate Studio with an Orchestrator license. Please request a Studio license if you want to do so. If not, install Orchestrator on your server, license it and then Acquire a Studio license from Orchestrator.
You can also check this topic where I gave a more detailed explanation: