Account suspended due to Vodacom's error

I had 2 contracts with Vodacom and in July I cancelled one. End of July my debit order was deducted, then end of August and September no debit order and my account is suspended. I had to phone Vodacom accounts several times and each time with a promise of call back. After about 10 calls I received a call from Vodacom and is informed that somehow they changed my debit order details to another bank and the debit order was rejected. I never requested for a change of debit order only to cancel 1 contract. I paid the 2 months (aug & sept) subscription but still my account is suspended because I did not pay the penalty fee of R100 for the debit order that was rejected. Why must I pay for that it was not my mistake, I will not pay for Vodacom's mistake. I again requested several times for a call back but now they ignore me. My next step will be to lodge a complaint at the consumer council and see if that will help.