HDFC Bank — credit card - blacklist

Address:

673004

I have been using HDFC Credit card for over two years. My card has been blocked by the bank few months back without providing any proper notice. \

When I contacted the customer care, they mentioned I have used my credit card for 'Certain International Trasnactions'. When I checked my statement for the said period, I could see it was used in 'iqoption' app. The transaction itself was made by mistake by me. Upon installing the app they needed to add money of $10, which i was simply trying but got accepted by the bank without any authentication (CVV/OTP).
There was no response from the bank team no matter how many times I contacted them. They always replied with the same message.

I tried applying for a new card after several months. The application was rejected by the bank and seems I am permanently blacklisted. There is no assistance from bank's side. This all for a transaction of such low value.

They doesn't hear the feedback from customer's side. They have blacklisted me without going through my usage/repayment history. I have never missed a due date of payment and still this application has affected my cibil score. I don't know what the corrective measures are the HDFC has for no reason messing with my credit score. Very poor response from HDFC Team.