Angel Tips Nail Spa

Went to get a manicure/ pedicure and paid $37.22. once my nails were dry I got up to leave and got asked did i want to leave a tip. i said no I don't have cash on me, ( mind you i just paid. She says oh do you want to go to your car and get cash. i said no i just paid you, she then insists she void my transaction and recharge me including a tip. i said why would i do that when i already paid and can tip next time. Literally was hounded for a tip when I just paid you almost $40. No one else was hounded about leaving a tip but i was, and was the only minority in the nail salon at the moment. I totally understand that this is your job and tips help, but harassing someone about a tip is way out of line.