Being ripped of by Netstar

I had a contract with Netstar from 2*** which I honored until it expired. Netstar however continued to debit on my account for the next two years without ever enquiring with me if I was still interested with their service. Recently I blocked the debit order from my bank account and I received a text message instructing me to settle the account in arrears within 24 hrs or risk being handed over to credit bureau. I then contacted Cecily on *** and her response was that as of 2012 my contract was on a month to month basis of which I don't recall agreeing to such thing. I then explained to her that I'm not prepared to pay any money because as of my knowledge my contract with Netstar ended two years ago. Cecily then informed me that she will continue with the process of taking legal action against me should I not settle the amount stipulated.