They diagnosed the problem well. The fridge was too warm. Melting the ice fixed it temporarily but 3 days later the problem would come back. Based on my GE brand, they knew the control board and thermostat commonly fail. There was a more experienced guy who came first and diagnosed it. He needed to come back with the parts. A less experienced person came and replaced the control board. The problem came back after 3 days. The guy came back and also replaced the thermostat, I think. He said they normally buy them together and replace them together. He replaced it and then it worked. They just charged for 1 visit plus the parts. It was a few hundred for the parts and maybe a 100-150 repair fee. The control board was a few hundred dollars. This happened in 2020-06.