I have a Kenmore bottom freezer model 79571302012 [made by LG] about 2 yrs old. When the freezer fan turned on there was a clicking noise and ice built up in the back of the freezer. Removed the ice with heat and the clicking stopped. About a week later the clicking started again and became louder over time and finally a week or two later the whole refrigerator stopped working. The refrigerator sat for a day unplugged. I plugged it in and it started up and was working fine, no clicking. About a week later, the clicking noise came back. Its been a couple of days now and the clicking noise is getting louder. Whats wrong?