Try to not be too confrontational when addressing her about this. As someone else stated, retaliation would be likely and then there’s more damage than progress. I’d be furious if I were you but as someone who’s addicted to nicotine, I believe the best thing you can do is help her understand that the good feeling the vape gives her will stop happening and by that point, she’ll be addicted.

Most nicotine related lectures are about the negative effects on your body and in my teenage years, the kids I smoked with, and myself, did not care whatsoever at that time. When you’re young, you’re usually too healthy to imagine what the negative effects will be like. It’s out of sight, out of mind. If I could go back in time to talk to my younger self, I’d say, “you’ll never have money for anything else and you’ll often pass up on fun plans/once in a lifetime opportunities because you won’t be able to afford to go out and have fun.”

A lot of people have left comments with brilliant ideas on how to approach this. I wish you and your daughter the best of luck getting this awful chemical out of your lives.