Blacklisted unfairly due to ****py service

I paid my account in full untill the end of the 24 month contract which ended 31 October 2019. Gave notice of my intent to cancel 3 months in advance and submitted all on the portal as prompted by the operator. Still to be blacklisted for R1000 that I apparently still owe. In July 2020 they finally credited this balance but still have not received a paid up letter after requesting it numerous times. I am absolutely fed up and dont know what to do or who to phone to get my credit reinstated. Completely unfair! I have been declined due to Telkom doing a absolutely ****py job. They do not give a damn and I am being punished for a service that I paid in full! I want compensatiin from Telkom!! I WILL NEVER USED TELKIM EVER AGAIN!