Mold on rim of Fireball

I occasionally drink Fireball with my friends when we’re having a night out. Please don’t judge me, I know it’s a terrible alcohol for NUMEROUS reasons, I have better taste 99% of the rest of the time, but it’s the 1 tradition we have. So spare me any judgement with that.

What I’ve become concerned about is that over the past year or so, every time we buy a brand new, unsealed bottle of Fireball, we find a black substance in the ridges of the rim. It’s happened 3 times in a row now and the substance I am almost positive is mold. Every one of these bottles I am positive were new bottling and hadn’t been previously opened. Want to get thoughts from this community.

I just wiped my hand around the neck of the bottle my friends and I just opened and this shows how much of the substance is on the bottle.