i do not know enough about the nk65 to be of much help, from your symptoms it seems that the UC is working as intended and the board get power, just that one or both of the usb data lines are disconnected/defective, although saying that i make the assumption that it uses USB2 over USB-C and not USB3.1 or 3.2 then it would have many more data lines than D+ and D-

so depending either try to RMA the board or open it and check if the usb is on a daughter board, and it that board is plugged in correctly. i would expect NK to be able to help you better than us on such a recent board though.