HDFC Bank — Money deductions without prior information and also not taking any confirmation from the customer

I am using HDFC bank credit card from past 3 years. For the first time i took the card they have not informed me regarding One assist mfee and they directly deducted the amount and when i asked for cancellation and refund they have not responded nor refunded my amount. Now i have upgraded my credit card and even before I make any transaction again they charged One assist mfee with 1899/- without taking any confirmation from my end.
I did not expect this kind of irresponsible response from such a reputed bank. I would like to cancel one assist feature membership and refund my amount