Vodacom overcharging and not assisting

I have received the worst service at Vodacom and they charged me more than what was discussed. On the 16th of January I took a contract for 2 iPhones for R750 for both phones, the consultant told me that there would be an amount deducted and I told her to debit on my Capitec account which I got debited on my absa account so the payment bounced. I called Vodacom to make payment the advisor told me to pay at Shoprite which I did but then my phones got blocked and when I called in they told me my account is in arrears which didn’t make sense because I agreed for the debit date to be on the 10th each month. Vodacom called me to sell me insurance and I told the advisor that I can only start the insurance in March because I’ll only have finances for it then but on the 10th of February I had a deduction of R1547,13 from my account. When I call in or ask for a manager no one is able to assist and I’m told there is no manager at work.