A few days ago me but not always noticed that one of the two the L2 button fully to its original position back, I thought that possibly from the guide button has jumped and therefore "pinched", so I did the controller opens ,
In short, the axis of the button was just broken out of the guide but not easy, what was the reason for jamming. The entire key is molded from a single piece of cheap plastic in order to save costs, if I remember correctly was the axis of the PS3 controller nor of a metal pin.
Sorry, but Sony so nothing will. The controller's otherwise quite good but save at such places is botched.