RBL Bank — Deduction of money twice and not refunded

Address:

Mumbai

I swiped at an hospital but actually amount was deducted twice in my credit card . I went nad asked about it to the hospital account department who denied of receiving payment twice .
I than immediately informed customer care of RBL Bank Super Card and did send a mail . They send me dispute form to be filled which I filled and mailed them back but than after that there was no reply to my mail and with several calls done to customer care who also always asked about the problem and than never solved it but always was said that we have registered your complaint. I kept on trying for the refund of my money till 1 year. Eventually at the end after several unreplied mails to the company I stopped the payment for the amount which was deducted twice, I got a mail that now the time limit has passed so we can't refund the money so please do the payment and the bank kept on adding interest on it .
I still.wonder why should I pay the money which I didn't spend and I believe I took action immediately and it was company's fault not to take action in time.
Now the company's executives are calling and harassing me everyday for the payment which I am not supposed to pay .
Kindly help me out in this case .