Harrassing and unprofessional cellc employees

I app**** for a cellphone contract with cell c, and my surprise came month-end when I was billed. I was also billed for an additional simcard contract. Why would I apply for a phone contract that comes with a contract sim and also take an additional contract SIM of the very same network?. Ever since then I'm getting harrassing calls from cellc unprofessional consultants such as Teboho@contractors and mbali@collections. All I'm asking is for them to cancel the SIMcard contract that does not exist so I can continue paying for the device. Well nobody can help me from inside cellc, so how can I help myself when I'm not even working there....I have sent the affidavit since last year September including supporting documents, but till this day I haven't even received even a case no.