James. Makesure your paint is not to thick. I found this online. Maybe it will help
AIRBRUSH DOESN’T SPRAY PAINT
This can be caused by many things; the most common are a blocked nozzle (due to poor cleaning), a loose needle chucking nut, improper/low air pressure and the paint being too thick
Blocked Nozzle – Clean or soak the nozzle
Needle not Moving with Trigger Action – Check and tighten the needle chucking/locking nut.
Paint Too Thick – Thin paint with appropriate reducer to a milky consistency
Pressure Too Low – Sometimes the paint can be slightly too thick and the pressure is too low to atomize. Increase pressure.