Wrongful credit listing after many year of being loyal to Cell C

Cell C requested to upgrade my contract but instead they mistakenly opened a new voice line. I then requested to cancel the new line and again Cell C took over 3 months to collect their device. My contract was finally cancelled after a long battle and numerous escalations. To my surprise, I am now listed on ICT as bad payer for non existing contract. As a result I am not able to any credit. I have on numerous accusation requested Cell C to update and write off my account and to this date I am still suffering due to Cell C's mistakes. I have since stopped doing business with Cell C. I have been a Cell C loyal customer for over 48 months, paying them R900 pm for 48 months. Now I am her as bad payer because of their *********** agent.