Refuses to process cancellation

Once my Telkom Mobile contract ran its course, I decided to cancel it seeing as I now have Fibre.

On the 24th of July I submitted a cancellation form to Telkom, requesting the cancellation to take effect as of the 31st of August (well more than the 20 business days notice required).

I never received a response. I attempted to contact them further, but at no point did I ever receive a response to any e-mail I sent to their cancellations department.

I then received my bill for August, which claimed that I would be billed in September. Obviously, they hadn't processed the cancellation. I got in touch with their Facebook support, who, for the first time, actually answered me. They requested that I submit the cancellation again, to a different e-mail address this time, and said that they would follow up on it for me. They did not, so I contacted them again, and I was asked to submit the cancellation once more. I did. I still haven't received any response to that.

Today Telkom debited my account for the month of September. I haven't used my Telkom internet at all this month, in fact the router has been packed away as of the 31st of August. I did everything required of me to make sure the cancellation was processed - I submitted it well in advance, to the proper address, and after that, ended up submitting it again multiple times at the request of Telkom support, all for nothing. At this point, I'm starting to consider this to be theft.