Why must I pay

I have obtained the full amount due from vodacom to settle my contract and convert to prepaid.<br> The full amount was paid, contract converted to prepaid. done.<br> <br> Now I get an email stating I owe them money!!! How the hell can this be possible? If you quote me to cancel my contract and convert to prepaid all should be included!!!! not my fault if you guys are asleep??<br> <br> Resolve this matter now or I will take further steps. Any action will be defended. I will also report this to the consumer commissioner.