Bean42

So i just started vaping in hopes of quitting smoking and started with the smok osub 80w tc plus kit. i have it set at 42 watts. at first use it was fine but later in day when i hit it its to hot on lips to take a full drag. upon getting ready to go to vape store to ask whats up with it i hit ag again and it was fine. unfortunately after a lil while the problem started again. any ideas what could be causing this