LINE Cancellation ignored by Telkom

I have cancelled my Telkom Account Oct 2017, but continue to be billed. Telkom responded to my cancellation mail. "We hereby acknowledge receipt of your fixed line Customer Contract and Service Cancellation. Your request will be attended to within 21 BUSINESS DAYS.??????From the 2nd of Oct 2017 till today 5August 2018 is more than 21 Business Days. They listed me with ITC as my account is in arrears due to Telkoms ongoing billing.I have contacted Telkom on numerous occasions via 10210 as this is the only way to query accounts at Telkom. An email address was given and all my cancellation details were mailed to no responce from Telkom. Impossible to resolve anything with Telkom over a phone!