Do I need to change my cosplay?

[Just a bit of context] For some reason, a lot of con creeps approach me and the person who takes me to the conventions (19m) just doesn't really care. It makes me really uncomfortable, especially since I am, and a badge on my lanyard clearly states that I'm under 18. I've tried talking to security, but they say that if it's not actually SA (even tho they try to take pictures from under my skirt) that they can't do anything about it.

My cosplay has a mask that covers my whole face, and short-sleeved dress that goes down to my knees, do I need to make the dress longer, or do I need to just ditch cosplaying until I'm older?

I apologise of this is the wrong subreddit, I'm just unsure where else to post this.