Telkom line never cancelled after many requests.

I have cancelled my Telkom line in June 2018. I have had to phone in many times. Every time I am told that the line is cancelled. Still I am receiving bills for the account. I have no phone line from May 2018. My last Ref nr from Telkom is ********** 8 on 24 Dec 2018 to confirm the line is cancelled. I dont want to be black listed because Telkom dont do their work. I am very dissapointed.