Charged after LTE cancellation and blacklisted

An LTE service was entered into on the 3rd of December 2014. This LTE was intended for use in my residence and the stipulated cost was advertised and explained to me to be R359.00 per month for 7.5 gigabyte day and 7.5 gigabyte night data usage. By 13th of December the system informed that all my data was used up in 10 days. When I spoke to the various consultants on 081180 I was told that the reason for the high usage of data was because there were apps running in the background (while I was asleep and the device was unplugged from power) I decided that this way of charging for what I was originally told would be R359.00 a month(for the usage stipulated) was a misrepresentation and I thus went into the Telkom shop at Cresta and cancelled the service on December 17th. I am in possession of the cancellation document which I registered with Gontse Molefe on the 17th Dec 2014. Despite this cancellation Telkom continued to debit my bank account every month for R359.00 and despite all my phone calls to 081180. This carried on every month and no matter what e-mails I sent to the various consultants Neo Letsipho and Fuzde Vyfer at the Telkom Store.