2019 Minnie plus 12v fridge issue

[xiques]

Hi guys
this is Jack, i just got this 2019 Minnie plus 27 BHSS, as brand new unit from dealer. it is equipped with ever chill WD-282FWDC 12V fridge. the issue i have with it is when plug in with 15 amp service( plugin at my garage), the lower fridge is work fine(after half hour i can feel it much cooler then room) but upper freezer is not work(fan is blowing, but after an hour even whole night still as room temperature)
called dealer service, but they seems have no idea (or too busy to get back to me):
if any one have any idea what is wrong with my fridge