I have a black Aurora Talentum that I really like. However it dries up on me as I am writing with it, and it does not even matter how full the cartridge is.... the line just goes dry and dry until ink stops coming out. I then take off the barrel, give few taps with the index finger's nail and it starts to write again. How do I solve this issue, it is a beautiful pen and I really like how it looks and writes just after the tapping. But I cannot use it at work anymore as I have to keep doing the routine regularly. Any help appreciated!!!