Unsatisfied Client telkom

We have been a client with Telkom for many years and last week Telkom decided to cancel all our contracts and delete the numbers. According to Telkom we missed to debit orders but they didn't check is that we have made payments every month for all accounts outstanding. This is pathetic. I have lost business and clients. Telkom never contacted us regarding the Telkom account and no one gave them authorisation to cancel anything. At this point I will be getting legal advise