Might be stuck with
juice, probably from non-use and it sort became like glue. I would suggest soaking in hot boiling water, just make sure you remove any o-rings or other plastics for a while or use some efferdent or other dental cleaner to really dissolve the
juice. If this doesnt work only thing I can think of is maybe somehow they tried to tighten things up and maybe they crimped the ceramic housing?
Must be something going around. I have the ceramic stuck on another of my atomizers. Hmmmm talk about practising what you preach, I haven't done that.