Near ********** behaviour

I started a data account at Telkom on the strict understanding from the sales person that it's a month to month arrangement. On notifying them in August 2015 that I would like to stop the service, I was told that it was actually a 2 year contract expiring in November. In August I gave them formal notice to terminate the contract on the day of expiry. In December I received yet another invoice for payment and upon enquiry I had to PROVE that I notified them to stop the contract. Fortunately, I retained the form I received when I notified them. In January I received yet another invoice and this I was told, was for usage during December while the sim was lying in drawer at home! I had no way to prove this and all these charges were deducted from my bank account. It would cost me a lot more to recover these near ********** deductions. Stay very far away from Telkom or go prepaid