Sounds like a previous issue I had. I was configuring a zebra thermal label printer. The print jobs were all messed up. I fixed this by changing paper size settings in the printer preferences. It was printing a regular paper in a 4 x 6 " label.
For some more help for techs reading this, I had an issue with the same printer not printing after it was powered on and drivers were reinstalled. The issue was the parallel cable was missing a screw to tighten it from a previous tech. When they say check cables first, check them first. You will save alot of time going from simplest to most complex solutions.