Disgraceful, pathetic Telkom

I am disgusted by how I am treated by Telkom. I canceled my contract, paid it up as the outstanding balance was given to me. Then boom received sms to say I owe. What is the meaning of month to month, I did not use your wifi since I canceled. How can I still owe you. Please sort this out as I will be going to the ombudsman if this harressment continues.I have not even heard from you since the last review so I am not hopeful that you will contact me at least.