Billing for cancelled services - 2 years later

In October 2015, I attempted to disable my Dstv subscription using the self service function. The system basically said I couldn't disable until there is a zero credit balance as we pay in advance for the month ahead. Therefore I waited till the end of October to disable it, and did so accordingly.

I then received a text confirming that I had disabled my services. I received no further correspondence from multchoice on my account after that.

In June 2017, I received a call from a call center agent, saying I owed R400. 20 months later. After no correspondence, no statements, no correspondence or texts during the entire 20 months. I requested that she investigate how this came about as I disabled my subscription and the billing is supposed to be in advance, and I did not get any messages in 2015 about owing anything or the fact that they were going to "suspend" my account due to the outstanding amount. I had zero correspondence for 20 months so I fail to understand how this is even possible.

I then received no further correspondence. I received a similar call in August I think, and again asked for a suitable explanation, I received none.

I am considering reconnecting my dstv. I trying to find out the costs involved, the agent insists I must pay the outstanding or produce a 2 year old text. This is unacceptable. I did some checking online, and it seems from around September 2015, there were multiple billing issues due to a change in systems, which may explain why they continued billing me, but did not send me a statement or any other correspondence relating to this for an entire 20 months. The agent was highly unhelpful in this regard, and I'd like to know who to talk to in order to get this resolved. I did not bother switching on my tv after I disabled it so I don't know if it was still running or not. But I refuse to pay for services I had cancelled.