Incorrect billing

On the 22/01/2018, I received a call from cell c offering me a pinnacle contract. I accepted the offer, however, when I received the handset on the 23/01/2018 I was not happy with it and phoned them the next day to cancel the contract. They sent a courier on the 25th to collect the handset and assured me that the contract will be cancelled since I returned it within 3 days. Later that day I received an sms telling me that my handset was submitted for repair, I then phoned cell c again and told them that I did not ask them to repair the handset but to return it and cancel the contract. The consultant I spoke to transferred me to the cancellations department who also assured me that the contract will be cancelled. A month later Ram couriers arrived at my residence to deliver the handset, I rejected it, didn't sign for it and asked them to return it as I had requested for the contract to be cancelled. I then phoned cell c again and asked them about this, again I was transferred from one department to another but finally got through to the cancellations department who reassured me that they have cancelled the contract. A few months later I noticed that cell c is debiting my capitec account, and I called them and asked them to refund me because I don't owe them anything and I do not have their handset or sim cards. They advised me to reverse the debit and promised that they have processed the cancellation. Now, almost 8 months later I received an sms from nudebt as follows: "ALERT: Mr/Ms Ntsizi, you owe Cell C , ND ********** 4 R100.45. Immediate payment is required to avoid your file being referred to a specialized dept. Tel ********** 656/Chat at www.nudebtchat.co.za."

I called nudebt and explained to them what happened but it turns out that I need to go back to cell c again, and I am not willing to do that because all they do is send me from pillar to post and then promise me something they won't do. I am not happy with the service I received and wish to receive a response from cell c management and for them to clear the listing on credit bureaus.