Listen closely and see if the compressor is short cycling. Keep everything quiet and see if the compressor comes on for a few seconds, minute, and then turns off. If that's happening, I bet the air divider under the inside shroud is misaligned letting nice cold air get sucked back into the supply, and triggering the frost detector thermostat. Happened to mine 3x's. Field repaired 3x's. Bad design.
2019 Jayco Greyhawk 26Y
2018 Forest River Sunseeker 2420MS - sold
2015 Jayco Greyhawk 29MV - sold