Stay away from Telkommobi

My contract with Telkommobi expired on the 3rd March 2018. I emailed cancellation of the contract on the 1st Feb 2018 with effect 3 March 2018. After months of constant telephone calls back and forth and not getting anywhere they handed me over to NuDebt to collect on the "arrears". As I didn't believe I owed the money I have continuously stopped the debit on my account costing me R40 a shot. Apparently my account wasn't handed over for debt collecting but to run the debit orders. I don't feel right that a 3rd party can take money out of my account, however according to them this is legal. I eventually had enough and spoke to a consultant on the 19th June 2018 who advised that if I pay the money owed they would leave me alone. I duly paid the same day. However NuDebt keep on deducting money from my account. After speaking to NuDebt today it would appear that until Telkommobi actually tell them to stop deductions, they will keep on deducting which means I keep on paying the R40 to stop the deduction. In 4 months I haven't managed to get anyone to assist me. It's like fighting a losing battle. I gave in and paid the money even though I don't believe I owe it and yet I am still paying the price for having ever had a contract with Telkommobi. I am so disappointed and at my absolute wits end. I have no idea where to turn next.