I have an old (over 20 years) mont blanc pencil. The lead does not advance unless you take off the cap and then twist the little silver ring just under the eraser. I have been to the local mont blanc store several times. One salesman took the part with the silver ring off another pencil, put it on mine and it worked. He said to stop by occasionally because replacement parts were rare. So, last night I stopped by, different sales person compared my pencil to a new one, said mine was a fake. In the new model that part scress onto the resin barrel and in mine it screws onto a metal part that is glued to the barrel. DIdnt help to explain everything else that happened. Can anybody help me get this fixed? This is my first post so I apologize for the length and lack of sophistication in explaining this problem