One Assist — I want to cancel the subscription

My younger brother recieved a call from the company salesman and he said he was from icici bank and told everything about the debit card insurance to my younger brother and then my brother just accepted to the scheme without consulting me, they told a charge of 1899 per year, but according to me i am not willing to spend money to buy this insurance plan, so i kindly request you to cancel my subscription plan.
Mobile no: [protected]