VL Triton II why do i have to re- my paintball gun everytimg i shoot it?

Everytime i shoot my paintball gun it does re- its self i have to do it. instead of it going "pow"(When i shoot it) it goes POW POW POW really fast idk whats going on.. If anyone can help soon because i am going paintballing with my friends and i want it to work properly. thanks