FX Dreamline - second hand heavy mystery.

This on reddit:

While shooting one day, she jammed on me. I removed the barrel and cleared the two pellets, unfortunately it dry fired without the magazine or barrel on by accident. I reassembled it and tried to fire and it just clicked, cleared the pellet again and it still clicked. So I released all the air from the tank and regulator, refilled it, but now once the regulator hit 100, and the tank hit 100 the regulator was creaping past that mark as the tank filled, once I seen the reg. hit 160 I stopped the tank only got to like 180. Either way, once that was done I test fired it a few times it worked and then randomly jammed again, cleared the jam and it then it wasnt firing again. I unfilled and refilled the tank and attempted to fire with the same result, I done this like 3x, btw it had dry fired again after one of the fills, so I decided to give it a rest for a few days.

It sounded like valve lock maybe, but after lowering the pressure he said the regulator says 50 bar, and the gun still won't shoot. Any ideas? Broken hammer spring? Broken valve? Not holding his mouth right?