Samsung RS2533SW, side by side refrigerator....

Question

My freezer side works good but refrigerator side is unable to thaw ice autoamtically and thus tempt goes to 58 to 60.If I clean the refrigerator by taking it outside and clean with water,it would work fine for a week or so.
Another problem occurred now. The child lock remains locked. Kept pressing button but would not react.
Have changed the motor fan. Samsung tech support is useless. The local service man was also useless (charged $100) as he said to change evrything including circuit board which I did.
Can anyone help. Thanks