Incorrectly billed for data resulting in lines being cut

Vodacom incorrectly billed my husband for data usage. I disputed the bill. While all of this was in progress they kept on debiting our account for the monthly premium and the amount for the data usage. The debit orders were un successful and then they decide to cut all of our lines. They finally issued a credit note for the data bill. This whole thing was caused by the incorrect data bill so why hasn't our lines been activated. Why should we now pay for the months that we could not use our phones. Had they debited for their normal monthly premium everything would have been on track. It's absolutely fraustrating as everytime we call we have to explain the whole story over and over again. This matter has still not been resolved and we have been left with no cellular service for almost 4 months now. We have been loyal customers to Vodacom as all our contacts are with them. Really dissapointed with their service.