There is no such thing as a USB-C port which will take thunderbolt or an 'approved Thunderbolt port'. USB-C is USB-C. Thunderbolt is Thunderbolt. A Thunderbolt interface will also accept USB-C devices, but a USB-C port will not accept Thunderbolt devices. So the real question here is whether you do have a Thunderbolt port, not a USB-C port. They may look physically the same but they are very different. If you have a Thunderbolt port, then if it is anything like my Dell 7910 or 5810, you need to enable the interface in the BIOS, and also switch off any security to just allow any device. Then it should work fine. If you have already done this then, is it seen as a Windows device, without even worrying about Presonus for the moment. If it is not seen in Windows then you either need to install driver software for the Thunderbolt interface, or something else is wrong.