Reliance Trends — even after the 50% discount on cloth, the full cost amount was taken while paying the amount.

I went to buy clothes in cine mall in kota (Rajasthan)'s from reliance trends. There i got 50% discount on clothes. Then i took the clothes and went to the counter, i was not given 50% discount and the full amount was taken. When i complained, the staff there said that 50%'s discount on our computer has not been updated yet. Give us 24 hours. But after 24 hours our problem was not solved.