Replacement fridge

I am having a problem with my Dometic refrigerator, on hot sunny days it won’t keep the freezer frozen. Would it be possible to change this to a different model or would a fan on the inside help fix the issue that I am having? I was thinking about getting one of those eBay fans for the inside or I have seen solar fans for the roof vent?

Help!

Are you sure the unit is level?

Yes my camper is level, I think this is more a issue where it can’t keep up with the heat.