When I cap this Rotring Newton FP, the pen gives an audible "click." However, just slight pressure such as attempting to clip the pen to your pocket results in the cap popping off the pen. The cap stays in place when posted, so the problem is with the section, where there are two small square "pins" (can't think of a better word) which extend above the surface of the section and hold the cap in place. One of these pins seems to be less pronounced than the other, which is causing the problem in my opinion. I don't know how to get this pin to protrude more. Has anyone run into this problem before, and can you suggest how I can get this one working properly? Thanks. Dale