HSBC Credit Card — HSBC

Hi,

HSBC has been provided Add on cards on my primary cards. One of the add on card has been misplaced and misused. Because of this I got a dispute payment of 21,350 rs and I have submitted the dispute letter to HSBC. For this HSBC has been saying that I have to pay the outstanding amount and HSBC is not liable for the same.
How can I will pay when i have not used at all the card.

Kindly help me on this.

Thanks & Regards,