Scale issue with UCCNC

Hello

I'm recently having an issue with the scale on UCCNC (not an imperial to metric issue).

Attached is an example, the material size is 420mm wide and shows that in text on UCCNC and when I travel the tool out to the edge of the material in the photo its X axis reading of -210mm from the centre is bang on. However you can see on the preview image on the UCCNC screen that its way off both on the x and y axis by approx 30mm on all sides. I can’t figure out how the preview image keeps loading at the wrong scale but it says the correct material size in text. Its happening for all files now.

Any help would be greatly appreciated! Hopefully its an easy fix!