We have a 2024 seismic 403 toyhauler. So couple days ago my propane furnace stopped working in middle of night. Assumed it was the propane running out and changed it out. I have a Coleman Mach thermostat. I tried to turn heat on thermostat, heat won’t come on, if I turn dial to change temp even one degree above what the room temp says then screen goes black and won’t come back on unless I turn dial back to below the last temp I just changed it to. So if room was 70 and I turn it to 71 it goes black, can’t see anything on screen so i turn dial back to below the 71 that i changed it to and push knob the screen displays again but heater still won’t come on. I can turn it to anything as long as it’s below the last room temp i turned it to. The cooling system on it works. So playing with it reading online and I did like a reset and pushed knob and held for 12 seconds and then it basically resets, that didn’t work so so did 20seconds for heck of it. That worked, but then the next morning tried using heat and it’s doing samething. Had a tech come over and they switched the main and bedroom thermostat to see if it was a thermostat issue. It wasn’t, whatever thermostat was attached to main wires samething happened. We made sure the little switches behind the thermostat were correct, the little cool/heat/propane switches. We changed out fuse so that’s not the issue, propane is fine. Any thoughts? please help. We have had so many issues with this thing and we bought it brand new.