Kenmore side by side Refrigirator

The fridge is not cooling. I've had the repairman out twice now. The fridge stops cooling for a day, everthing melts. I call the repairman, by the time he get out to see me a couple of days later the fridge starts cooling and working. This is very frustrating because the repairman cannot fix what's working. When the fridge stops working the light still work and I can hearthe fan, the weird thing is that the water dispenser stops working. I know that the fridge is starting to work when the water dispenser starts working.