Ge Monogram Outdoor Grill Why My Two Years Old GE Monogram Refrigirator Became A Freezer?

Why my two years old GE Monogram refrigirator became a freezer? - ge monogram outdoor grill

My refrigerator is set at 6 degrees Celsius, but does not work. The bottom drawer and the fridge is freezing and vegetables. What is the problem? How can I make the repair themselves, without seeking the service.