Launch fridge trouble

[Cabingal]

Just picked up our new 24 Rls last night. They had the fridge running, but told us it was set too high and had iced up so they defrosted it. When we got to the campground it would not cool on electric after hours. But, it works fine on the gas. Since this is our only home for four months, we really need a fridge and hate to have to go back 60 miles to the dealer. It's not a fuse, hubby checked! Any help appreciated!