Debit order coming off twice

Decided to get a 2nd contract for my fiance at the beginning of January. I was told by Vodacom that my my first debit would come off at the end of January. They tried to debit my acc a day afterwards which was unsuccessful. At the end of the month (27th Jan) it was debited, where i was charged an additional R100 for a failed debit. Then this morning (4th February) it came off AGAIN!! I am furious and want the debit to be reversed (incl. R100 for the failed debit) as i was told the first debit would only come off at the end of the month! I do not want credit, i want CASH back in my acc!!!