Black listed by Telkom after I cancelled my contract with them

I cancelled my fixed line contract with Telkom in Sept 2020 and have the emails to prove it. I drew a credit score for myself and Telkom has listed me as a non payer after Sept 2020. I phoned their customer services. First they referred me to Nudebt, they don't have a record of me. Then I am told to phone 1023 and asked to be put through to Attlier Agency. At 1023 they don't know of Attlier Agency. What now? I have had fibre since Oct 2020 and have never received a statement or letter of demand to pay from Telkom, but I am black listed.