Airbrush disassembly help

I have recently bought a Badger Xtreme Patriot 105 airbrush, which I haven't used yet (other than spraying some air through it). I've been watching videos on how to disassemble the airbrush properly, so that I am able to clean it after my first use and all has gone well, except that I am not able to to unscrew the nozzle cap. In the video I watched, the nozzle cap came off with very little effort, but even I try to twist with a lot of force it won't budge and I have no idea how to get it off. Note that the airbrush is brand new (so it is not an issue with dried paint) and all other components of the airbrush have been removed.

Help would be very much appreciated.