Help with loading my UR824 and Cubase Pro 9

Hi folks, really hope someone can shed some light on my issue. I have tried searching and following YouTube videos but am still coming unstuck.

I am new to Mac and have just installed both the UR824 and Cubase Pro 9 on a Mac Mini using High Sierra. When I load Cubase it says that my Mapping Ports for UR824 are missing and when I look in VST connections it is not showing at all, only internal or HDMI output. When I import loops, audio plays through the Mac on internal or through TV when selected HDMI but not through my monitors connected to the UR824 (The UR824 is not even available as selectable). This is the same outside Cubase and I am unable to select the UR824 as a sound output to use my monitors for streaming services.

I believe that I have installed all the correct drivers etc so have no idea what else to try. I’m probably being thick as hell but as a new Mac user & new to the recording game it’s stumped me for the last few hours.

Any help would be greatly appreciated :v: