I think pixel is having a hard time getting the lid off, so I'm not sure how far a pin might go. I normally just to be sure I clean the tip, where the gel is dispensed from, of any residual gel after every use with a paper towel.
Maybe you can even soak the top portion of the tube (or just the lid area) in very warm water to try and soften the gel that is keeping the cap from coming off, and then try taking it off.