HDFC Bank — Credit card

Address: Hdfc bank. varkala branch

I went to hdfc bank requesting to close my credit card. The bank employee had asked me to login netbanking on their system. Then he said dues are cleared and requested to close credit cqrd. But after 2months i started to receive balance dues. I inquired about the same on the bank and the response was very bad. They said they Won't deal with credit card. And asked the security not to allow me to enter inside bank. I cannot clear dues via netbanking because the card option is blocked. But iam receiving monthly penality for not clearing duees. Bank employees are very ride and they are asking me to call helpline number. When i call helpline number, which is out of coverage and not reachable. Where can i complain?