closed account yet still receive bill

I closed my account last year, paid in (what I thought) full at the Rosebank mall (2015). The account was not settled or closed as I then received a bill for money outstanding. I then paid this amount of R 723.11 in full at the end of January, as I received a letter of final demand and settlement. <br> I now have an email stating that I need to pay R 209.98. Where does this come from? I am beside myself as I requested that the account be closed and to provide the full settlement amount from Vodacom at their shop, in order to do so. I also understand from the letter that I received for this R 723.11 that this would be the final payment. I cannot get through to anyone when I call Vodacom and will not be paying a cent more... these contracts are nothing more than serious money making schemes!<br> Very disappointing as I know that this also affects my credit record and I do not have any control. <br>