How to fix or remove a stuck cone shape airbrush nozzle
The Taiwanese factory sent me an email to help me fix an airbrush having the nozzle stuck in the head cap 15 years ago.

The solution is to use a needle-nosed plier:


Place the needle-nosed plier's left tip on the left edge, and the right tip of the needle-nosed plier into the nozzle's hole. Grip using little force.
Place the needle-nosed plier's right tip on the right edge, the left tip of the needle-nosed plier into the nozzle's hole, grip it using little force.
The nozzle falls off!