HDFC Bank Bank Womens Gold Card — FALSE CASHBACK PROMISES

I have an HDFC Womens Gold Card No [protected] and I had used the same for purchase of my family air tickects for the holidays. The purchase was doen on assurance of the customer care officer that I shall get a cash back of 5% of the amount upto a max of Rs. 1000 per month provided the bill for the month was more than 35000. This being a good assured offer I opted for the same. However, when the stament for the next month came theire was no cash back offered.
I have been repeatedly trying and have lodged a complain with them, howevr they are just avoiding my compalint and giving me lame excuses.
As they have cheated me I would like to register this complaint against them in this forum. I would have got better deals buying tickets on www.makemytrip.com or other similar sites. Just by the words of their customer care officer and after confirming with him more than twice, I took this step.
Now they tell me that the terms and conditions are not valid for this card.
By doing so thay have only shown how their team is cheating its customers.
Please take neccessary action against such fraud credit card issuing banks and get me by due cash back with compensation for the mental agony they have given to me and my Husband

Isha sharma.