Seventymm.com — Charging my CC without my permission

Address:

Bangalore, Karnataka

I had taken membership of seventymm.com for DVD rentals with member ID 635856 on 2nd July 2011. While taking membership I had paid by my credit card. This membership was for three months. I had ordered movies from seventymm, and most of the time DVDs have never ran. I had made many complaints and for that they would just increase the membership days. So, I didn't want to continue their membership. When their customer care executive had called me with new offers for renewal, I had told her that I don't want to continue their membership. On 7th October, my account got expired. Seventymm charged my CC for renewal on 17th October without my permission. When I called their customer care to ask why did they charge my CC when I had told them I don't want to continue they told me they had put a check mark for auto debit. I never opted for auto-debit when I took their membership for movie rentals in July. That also they did it without my permission. When I asked for a refund, they first told me money cannot be refunded instead I will have to buy some products from their site. I told them since it was their mistake, they have to refund my money then they told me they can refund only after 15 days.
From 20th October, that is since last two weeks, whenever I contact seventymm.com, they send me the following nonsense mail:

Dear,Nabanita Das

Subject:Refund request Member id:635856

In reference to your mail, Please be informed that your account has been canceled and amount reversal request has been forward to finance team they will check and do the need full shortly.

Thanks and Regards,
Amrutha
Seventymm e-mail support

Please suggest me what to do. 15 days are over and I still have not receive my refund.