Vishal Mega Mart — Regarding bad behaviour of Vishal mega Mart staff persons and not giving the scheme

I have gone to the Vishal mega Mart in Meerut and there was scheme on clinic plus shampoo 340ml with MRP 199 and there were two shampoos there one of 340ml and other was around 350ml.
There scheme was attached that the shampoo whose MRP is 199 and is of 340 ml is having discounted price of rs 172.
I have purchased that and get to the bill counter with my other necessities.
2 Billing counter was operating and I was on one counter on which one ma'am was there and she was asking her senior to resolve the issue agin and again as she might was new employee.
She called her senior and they have made the bill and considering that shampoo on MRP 199 and billing to me at rs 199.

I went again to that scheme counter that if I am right or not and discuss ed with one of the staff members there. He said that you will definitely get these scheme. Then he come with us to the billing counter and said to them to give my 27 rs back as scheme was to give that shampoo at rs 172.
But they said that shampoo will be of 199rs and if I want to purchase then I should purchase at rs 199. I will not be given shampoo at 172 rs.
The ma'am who has billed my products said that she do not know me and she had not billed.
I come back as I have never seen such behaviour of any Vishal mega Mart persons and decided to complain online.

Very bad experience.