HDFC Bank — cancellation of one assist membership

Cancellation of one assist membership
I am a hdfc bank credit card holder. The bank has auto debited rs. 1899/- from my credit card number ending with 0627 without my concern on date:22/11/2017. I am not interested about this service and don't want this membership any more. So cancel the membership and refund this debited amount of rs.1899/-

Oneassist relationship number : 633321
Name :- amaranath gorantla
Mobile no. :- [protected]
Credit card number ending :- 0627