Is it because I’m the trial version?
Welcome to the forum.
Please make sure that you have the latest versions of Groove Agent SE 5 and the Groove Agent SE 5 Content installed. These can be found by clicking the Cubase Pro 12 icon in the Steinberg Download Assistant.
The trial versions of Steinberg’s products have no limitations. They all behave exactly the same as the paid versions for as long as everything has been installed correctly.