issue with account settlemet

During month of January 2015 i phoned Multichoice to have my decoder switch ofF, which they did, nothing was mentioned of a payment to be made. During June 2015, i received a phone call from a collecting company on behalf of Multi choice stating i still owe Multi Choice. I the phoned Multi choice for an amount which i paid on the same day. After that i received numerous calls from their collecting company, I spoke to Multi choice and they promise to fix the problem as it shows settled on their side. Today i received another call, and i phone Multi choice had to hear the same story that they escalating the problem. I insisted i need to speak to manager but as usual was not available. A lady with the name of Prudence promise to solve the problem and sent me a letter stating that my account is clear. She promise she will do it before 1 oclock and call me back, which she did not. When i phone back at about 2 oclock she was not avialble and no manager avaialable