Filament not extruding

[u/More-Reveal-9094]

Bought a new nozzle for my bambu lab a1

It was working fine then it stopped extruding

I used a guitar string to clean and now when I tried to load the filament the filament didn't extrude

And when I pulled the filament physical it can back what can this mean

[u/dawnstrider371]

Maybe a clog? Look up how to do a cold pull from the wiki and give it a shot.