How do you fix a pistol pellet gun?

Look up on the Web under "Air Gun Repair" and find a shop closest to you.

If you don't want to spend any money on repairing and you want to repair it yourself, you can just take the gun apart, find whats causing the trouble, and decide what needs to be fixed or replaced. My stinger p36 handgun would load the bb in the chamber then get stuck... so i took it apart and then found out that my gun has been damaged when i dropped it. that the easiest way!