Samsung fridge not cooling effectively

I have a Samsung fridge that most of the appliance repair firms in town refuse to due the poor support technicians get from Samsung. It had been working for the first few months I got it from my parents but now it's not cooling properly. The override controls are set to cool at 38 degrees in the fridge but it only registers at 58. The fridge isn't full (for this purpose since everything will go bad faster if it's not cooling properly) and all the dust in the back around the coils had been cleaned and dusted before it was placed in the cavity. I already tried turning it off and on again, I turned off the breaker switch because I can't physically move the fridge and it still didn't fix the problem. The freezer appears to be working just fine for some reason but the fridge isn't.