Discovery cancelation nightmare

I had a Discovery Credit card as a secondary card to my F N B card. I experienced ***** on my Discovery Card and reported it. Discovery was unwilling to reverse the payment and I had no option but to cancel the card. As such I had no further dealings with Discovery Bank. I am being billed R200 a month for an account I have closed. I am advised that I still have an account that was not closed when I canceled my card. No mention of this was made at the time of cancelation. I have not had any transactions on the account and can not use it. Discovery refuse to refund my monthly payments since cancellation