Apopheniacal 2 points 1y ago
To add to this comment (because the summer training is an excellent point), your DM's email/phone number should be in the back on a poster, or on the little store cards (if your store has your store manager's info out in the lobby).
I would try to talk to your store manager one more time about this situation, record the date and time, and if nothing gets done, immediately go to your DM about it. That will start a paper trail if things need escalating.
You don't need to be talking to someone twice your age who is already disrespecting you, and will likely get more hostile if you try to address issues like this.