Ylg India — bad service and interaction, wrong information conveyed to the customer

I visited ylg for the very first time on 21st dec, 2017 to opt some services.
I have the following complaints:

1. Wrong information conveyed to me:

I booked an appointment for the same. I had a coupon code and asked them if i can avail it. The receptionist said yes.

After visiting the salon and opting the services, they did not allow me to use the coupon as i took a combo service.

No where in the communication, they said that if you use combo service you won't be able to avail the coupon.

I feel highly cheated, and a good way to grab a customer.

2. Painful waxing service:

I opted for a waxing service, and the lady named 'hathija' was providing me this service.in spite of repeated requests to her that her procedure of the service is quite painful, she did not bother about it. Rather defended herself by saying if she follows this rigorous procedure of waxing, it won't be harmful/painful to me.

To be very clear, she was extremely speedy in removing the wax strips. This was causing me severe pain and my skin was turning red.

3. Caused me skin patch on my right hand:

Due to fast removal of the strips without any break, caused me a dark patch on my right hand. It was paining the same day a lot. But since next day i see a dark patch on my hand.

Resolution :
Who will help me to cure this after this harsh procedure of waxing the customer hands?
Even after purchasing a coupon, i could not use it. Please help me resolve this.