Regarding Misbehaviour of Internet service provider

Hi, I have a Internet connection provided by one of the reputed company. Of late, i was fed up of the service they provided and raised for the cancellation of the service on 17-5-2015 by calling the Customer care to which they responded saying i would get a call back for the same and then nothing came from their side. the lady also told me to pay the amount that was there as due after which the connection would be closed. There has been e-mail conversations for two months(starting from June 6th) asking about the bill amount being high and about cancellation. Two months of them torturing me to pay some amount (which was really out of expectation) and then finally I paid the money on 26th July. My understanding was, since the request was raised for cancellation, I just called them on Sep 21st asking them why calls were still made even after payment to which the customer care executive told he was sorry about it and he will close the service permanently. Again after 2 months now, they have claimed another 2000 rs as bill amount. I have mails for the cancellation and a call recording made on 16th Nov where the customer care executive agrees that i raised a request for cancellation on 21st Sept. These people are now torturing saying, they would go to Civil Court for the same. Please help me