Terrible service from Vodacom!!!

I work for a security company, and uses our Vodacom cellphone in the control room. The owner also uses a Vodacom cellphone for business purposes. Our telephone lines were cut on the 7th, 8th, 13th, 14th, 21st and 22nd of August, because according to Vodacom, our accounts are in arrears. The fact is that the accounts were paid in full on 28 June and on 31 July. It was paid in to the Vodacom Debtors account, but this was mentioned to them when they cut it off the first time. I have made numerous phone calls to Vodacom, sent numerous emails with proof of payments, and spend hours on the phone explaining the same thing over and over again. How long can it possibly take to allocate the payment to our account? The owner of the business is on the verge of cancelling all contracts with Vodacom.