Airbrush Gun Troubleshooting

My airbrush gun is spitting large, irregular paint particles when I try to spray out product. How do I fix this problem?
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No makeup is flowing through my airbrush gun. How can I clear it up and get the product moving again?
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I cleaned my airbrush gun and assembled it accordingly, yet only air, but no product is shooting out when I spray it.
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I've been using my airbrush gun for a while now, but it's starting to feel a bit rusty. The trigger won't press down and pull back smoothly as it did when it was brand new.
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When I press down on the trigger for air without pulling back, makeup shoots out of my airbrush gun instead of air.
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My airbrush gun is creating a solid messy stream of makeup. How can I fix this?
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When I spray, an unsteady stream of makeup is spitting onto the face. What can I do?
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Should I clean my airbrush gun after each makeup application?
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How do I unscrew the nozzle on the airbrush gun?
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How do I take the nozzle out when it's been broken and fragments of it remain inside of the airbrush?
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How do I take the cup cover off of the airbrush gun?
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What should I do if I can’t get the needle back into the gun when I’m assembling?
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