Naturals — poor service and no refund provided

Address: Chennai, Tamil Nadu

Hi
We visited the Naturals Iyyapanthangal on 2nd June for a bridal package for my friend. One of the staff - revathy- suggested to go for three sittings of radiance facial, where the last two sittings will include manicure and pedicure.
She convinced us to pay the entire amount of 12k approx stating that otherwise we'll be charged more tax.
In the first sitting, my friend asked if she could get a threading done and she said she will do it and it's gonna be complimentary.
The facial was very unprofessional. People kept on coming inside while the client tried to get relaxed. The last pack was on her face for a very long time bcz revathy had gone out or forgotten. She came running and apologized to her. Post the facial, my friend asked her to get the threading done. She kept on insisting that the eyebrows, have to be thick and just the extras need to be plucked, however, revathy did her own thing and made it very thin. She was not at all focusing on the job at hand and was gossiping with the other staff members. Post the threading when my friend complained, she said that her eyebrows were out of shape so she just tried to style it.
Bcz of this horrible service, we wanted to get a refund of the rest of the amount paid as there's no way we want to go for another round of torture there. But the staff of Naturals are stalling us and not refunding. They are asking us to get the coupons instead. What is the use of the coupons if we don't want any service there bcz of the incompetent and inexperienced staff?
Just to collect money, they wrote something on the bill and collected it. Nowhere in the bill its mentioned that the amount is non refundable. It's been a month now and every time we call, they say that the area manager will call or the finance team will call but no one ever gets back.