Over Billing

My Cell C account has been over-billed in an amount of R194.00 ex Vat per month since the beg of Aug. I lodged a query last week. I have had 2 calls to say it was an error and will be escalated. My latest Debit Order has now gone off, R400 more than it should be! I also have not received my account as requested. How long does it take to sort it out and resolve the issue? I can assure you if my payment hadn't gone through my line would be suspended immediately! ***, ME PEENS