Upgration mess up

I had an existing account with vodacom and I upgraded my account with them in November, in desember I found out that the consultant did not upgrade my account but opened a new account. I have been struggling since then with my account.ever time I foned customer care they said that they can't pick up any account on my name but they debited almost double the amount that I was suppose to pay. And now now one can help me every consultant that I speak to keep transferring me to another consultant.