Still being billed for cancelled contract

My contract cancellation was sent over 12 times since September 2015 (to the correct e-mail address) and the contract was finally cancelled in January 2016. Telkom mobile is still debiting my account. I have contacted their customer service department on 3 occasions already and I am always told that it will be escalated - I have just received another invoice for April.<br> <br> The chat function on the website is useless (and Telkom is supposed to be a leader in the telecomms industry and the waiting time on the phone is too long (over 20 minute to speak to someone)<br> <br> Will some please contact me urgently to stop the debit order and process my refunds.