What do you do when your steering wheel won't turn?
First, try using a spare key that you don't normally use. If that works, your main key is probably worn down through normal usage. Also, check the tumbler. It might be worn down from usage, or it could have been damaged if someone tried to steal the car. Also, check the neutral safety switch or shift linkage—if it's not being put in the proper position, the steering and ignition lock can get affected.