2006 Chrysler PT Cruiser AC not blowing cold air

had my car to same mechanic three times for ac not blowing cold air. he has replaced the compressor 3 times as he said it was defective. he put on a new fan,blower,etc. but ac not cold air. have a 10 yr warranty on the compressor…what can be the problem

I think I have a clue…

Your mechanic is the problem.