Vodacom ******* billing

Appauled, Vodacom contract value monthly R1300 and then out of the blue billed R6700. After months of paying for Fibre with no service, a credit promised and then a bill of this magnitude. Vodacom then tries to justify the mistake after admitting their mistake. Who can afford an error of this amount. We have paid monthly without fail and after all my attempts to be sent a chain of mails brushing off the details by a senior person without a clear explanation of how their billing mistake has made this huge debit order. This is *******, you have gone against the CPA, you have charged for something you can't take the time to provide detail and each different engagement the next employee has a different explanation.