I have a new smok pen with prince coil setup. I have trouble with what I think is dry hits. It is my first vape. I can fix it every time by opening and closing the refill top. It seems to me that introducing air into the tank resolves the problem, but I have to do it every 5 or 6 hits because it stings the ____ out of my throat. Open and close the top and it hits perfectly again. Any ideas? It's very frustrating.