Router contract cancellation

I'm fed up with Cell C from last year September I was waiting for my router and cancelled up until to day it been a year now. Instead they forward my account to legal collection hence when I go to Cell C they tell that they don't know what happened. My name will be written under credit bureau because of Cell C negligence. I reported them on Hello Peter last time they called me and fool me that they will deal with this case up until today I kept on receiving call from 2 different layers demanding payment. Hammond pole laywer and other laywers group keep on calling everyday.