It’s so frustrating when someone refuses to listen to sound advice that will keep them from harm, but there’s nothing you can do. It does sound like your friend has had a break with reality to think a member of BTS found her and needs her to send him $! Is this how she normally is? Is it possible she is truly having delusions? Normally, I wouldn’t tell my 28 y/o friend’s parents, but you may want to due to her being this delusional and the amount of the money she’s going to lose.