I have a Maytag 20 cu ft. refrigerator that is about 7 or 8 years old. It has the freezer on the bottom, double doors Refrig on top. It was an is suppose to freeze to 0 degrees and refrig should be 38 degrees. It was working right but then thawed out last night... I shut the power down and then restarted it now it works but only 22/42.... what do I need to do to restore it?