Why won't my calligraphy pen work...?

I got a new calligraphy pen a little while ago and it worked great at first. recently its started to falter and stopo in the middle of letters and words and i cant get it to work for a while. i dont know if its because its worn out or the ink or what, but i need to get it working again soon because i need to fill out some invitations soon. i tried putting a bit of water in my ink (not all my ink, i have two bottles) and it flows better, but too fast, it makes it fruzzy after it dries and soaks into the paper. i don't know what to do. any help?