Account canceled a year ago handed over

I called Vodacom to move my account from contract to prepaid because my contract was ending. I was then told there’s an amount that would be debited month end then I would be moved to prepaid, I asked the call centre agent if this would be the last amount that would be deducted and she confirmed this. The amount was deducted and I was then moved to prepaid in the new month. After about 3 months I was called by the accounts department saying there’s an outstanding amount, I told the agent I spoke to that I was told there is no outstanding amount and I would be debited the said amount, wich was debited and I asked them to pull that call and call me back once they had listened and confirm what I knew. I was not called back ever since, until on Friday the 13th October. Mbd called to notify me Vodacom has handed over my account. I have tried to contact Vodacom, sent an email, posted on twitter to no success but I get smses from MBD. An agent from Vodacom confirmed that because they had a system change, they couldn’t pick up my details but my last debit would be going off on the last working day of April, which it did.