Billing SHOCKING AGAIN

Vodacom Business again with the BAD SERVICE!!!!!!!!!!! After trying to cancel a number for MONTHS!!! I did get a call from Vodacom saying the number was cancelled and I would get a credit for March, April, May, June. I have NEVER gotten the credit and now I am getting warning that our service is going to get SUSPENDED if we don't pay the June invoice which should have been credited in the first place.