SBI Cards — "Super saver offer, new delhi" ,HDFC bank

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Tamil Nadu

"Super saver offer, new delhi" fraudulent transaction from my HDFC credit card

I got a call from a person speaking on behalf of HDFC bank.he had all the details like my card no, age, residential address, date of birth, etc. And other personal information. he told me about the offer and gift vouchers which I would be getting free of cost as a part of HDFC bank esteemed customer.I asked again this is free of cost then he told it is totally free of cost for you because you have good credit history and you are a lucky customer, also the they told me that i will get super saver card it has 25% on every purchase, they ask my card details to them after that I came to know that rs. 5999/- Is debited from my HDFC credit card.also they tell me i will get a welcome kit with in 15 days.so for i did in get any thing from them.

I asked them to reverse the charges but they denied doing it.
Now how should I get my money back from those people? please provide me information and details of account number where this money is transferred and try to block the transaction.

This is really a very serious issue, somebody is playing with brand name of ICICI bank,
please do the needful.
Regards.