Bad public review of my name

Telkom has listed me on Credit Bureau and claimed that I am a bad payer, as a result, I have been struggling to take out any credit, I then decided to contact them, I spoke to an agent who for more than one time, she confirmed that I am not owing Telkom and that in their records, it shows zero balance, I managed to get this agent's email ********** I have been trying to contact this lady, with no luck, the last time I spoke to her, she said the billing department is trying to resolve this issue in as much as they also not sure why my name is listed, to them, it didn't appear as if I owe them, so I asked the agent if she may please email me my paid letter, to date, I haven't heard from Telkom, I am really frustrated