Hi, I suspect your drain is frozen , and you will need to add a drain heater.Do you have water freezing on the floor of the freezer and water dripping in the refrigerator,or just condensation in both compartments?
Just as you describe - water dripping in fridge and freezing on the floor/bottom of the freezer. Started after 4 years of no problems. What is a drain heater?
It is basically a heat transfer using a small piece of metal stuck into the drain to stop the drain from freezing.The part number you need is 819043.You will need to remove the back inside wall of the freezer and thaw the drain,the heater will need to be attached to the heater and put inside the drain.