Sounds like your chain vaping! Mine gets pretty warm too if I don't allow for some cool down time. What kind of battery are you using? Is the hybrid cap the brass one? No shorts anywhere? Which clone did you buy? Pictures?
Also, I don't know if it would make a difference, but the guy from praxis says to screw the cap onto the atty first, not super tight but snug, using the three post side next to the atomizer. But since the fill hole is there, I would probably use the circular side up against the atty so there is no chance of the posts on the cap getting stuck in the fill hole.