Telkom Ripping me off and not cancelling my service!!

This all began when I upgraded my LTE plan to uncapped. I was initially on contract as I received a free modem with my plan.My upgrade meant I would pay R849 per month instead of R349. To my surprise my first invoice was for an amount of R1600, I was informed that my contract was broken when I upgraded my plan and therefore I was charged for the full cost of my modem. The sales person did not disclose any of this to me .They then however confirmed that I was now no longer on contract but month to month. My specific question was "does this mean when I change to Fibre I can cancel at any time as im not in contract" I was told yes it would be no problem. Well Fibre was eventually rolled out a few months later and I was in the process of making the switch. I called Telkom on the 28th of August to cancel my service and to my surprise I was told I would need to pay my instalment of R849 plus R800 break fees. I informed the agent cancel the service but I am disputing the break fees. I called a few more times after this and on my last interaction I was told a manager would contact me. I have not touched their device or used the service at all since September and till now my service is still not cancelled, I am still being debited, no manager has called me and I am now paying for my Fibre and the Telkom LTE.