Bad Credit Rating Due To Telkom Mistake

I app**** for a Telkom Simple plan and i have been paying diligently for this on a monthly basis. The plan initially cost R399 per month so when i received my bills the amount reflected around R430 so i assumed that it was correct. Little did i know that when they opened this service they did 2 profiles for me one of the voice and a separate for the internet so my bill reflected a non discounted service. So for the last few months i have only being paying the voice bill even though my statement said DSL but excluded the data package. So in other words i was defaulting the data package and i only found this out when i go take out a cellular contract at FNB who tell me that i am a bad payer as my Telkom bill has been defaulted. After numerous calls to the call centre which is always 20m minute or more wait i had no joy so i went into the store at Telkom Forways crossing where the lady in service picked up the problem but she herself could not get the call centre agent to understand.I am very dissapointed that a mistake Telkom made is now affected my credit score and they cannot help me to rectify. I will be cancelling my service with them shortly