I bought a Vanilla mod today and it was working great all day. I had the guy who worked at the store (Eastern Vapor in Brighton MA) set up my coils and wick. Its a double coil with a Tobh Atty. It was working great all day and then started getting weaker on me and now it will barely heat up. I tried cleaning every part, and new batteries as well. I am using IMR efest 18650. Any suggestions? Thanks in advance.