contact which came to end end, i am still billed

I have several contracts with Vodacom, which would indicate that Vodacom was a choice service provider, but now I am really disappointed in their service. The contract on this no *** came to an end in March/ April 2015. I phoned and indicated that the contacted be terminated and that it be converted to a pay as go and to to date this has not been effected. I phoned the call centre, was told it was fixed, still this was not done. I went to Menlyn customer care centre and was told that on the system the contact was cancelled, I relaxed and to my surprise since August / September I have received huge bills on this contract. the initial reason for the cancellation was that this phone contract is used by my daughter and she has another contact, hence the request that it be converted to prepaid/ pay as you go. can I humbly request that all payments be reversed and that this contract be terminated as previously requested and number be retained as prepaid. <br> <br> regards,<br> <br> Mapule Phora