No right to debit my bank account

I had a contract with vodacom which ended in July, I called in in May to cancel and called in again in june to confirm the cancelation. The last payment was in July but to my surprise vodacom debited my bank account with over R400 which was even more than the contract amount of R255, I 1st phones in on the 27th Aug to qeury the debited amount and was told it was a premature cancelation which I disputed cause I know that the last payment was in July and she did double check and confirmed that it was an error from vodacom side and will request a reversal of the transaction and should take 7 days for the money to be paid back to my account. A week later I phoned again cause I hadn't received the money and was told the money was paid into my vodacom account and I have no idea how to this account works and I requested for the money to be paid back into my FNB account where it was debited from and the lady said she'll send the request through to accounts and this should take another 7 days and to this day I'm still waiting. I phoned in again and the gentleman told me the instruction was created for the money to be paid into bank account but cannot tell how long it'll take but I'll have to phone the accounts department in the week. I have a 4 months old baby who just finished her last formula today and I can't buy her the formula because vodacom won't refund me my money which they were not supposed to debit in the 1st place. Vodacom pay me my money, I don't owe you had no right to debit my account so stop making my life difficult by having to make follow up. No in question ***