UNWANTED UPGRADE

Vodacom phoned me on the 28th of Aug for an upgrade which I immediately said no to, but the guy just kept on and I later just ended the call. Not even 5 minutes later I got a sms saying that my upgrade was approved. I went to Vodacom Pavillion and the said it was done and gave me a number to cancel it, I phoned the number and the lady said she will cancel it and send me an email which I didn't received so 2 days later I was at Vodacom again and they said that it wasn't cancelled. They told me to open a ***** case which I did. Vodacom customercare emailed meand said it would take 10 days to investigate. They just have to listen to the recording ... how difficult is that. Last week I received my account via email and guess what the billed me for the upgrade, I emailed them and said I am going to cancel my debit order with which they have a HUGE problem and could phone me immeadiateley after that ... investigation still going on. This is now the 20th of Sept no one can still give me an answer. Emailed them again today they say it was given to various different sections and each one just passes it on to the next ......when I asked no one has listened to the recording yet....... HOW DIFFICULT IS IT TO GET THE RECORDING LISTEN TO IT, especially when I gave them the exact time of the phone call, AND come back to me. Never ever in my life will I take out a new contract or renew a contract with service like that!!!!!!!!!!!!!!!!!