Land line + ADSL not cancelled after 4 months

we cancelled our ADSL and land line in October 2017. We received confirmation and a reference number for the cancellation but we are still being billed. How can Telkom offer such patheticly poor service. There is no one to complain too. Call center takes long and does not resolve our query, we dont know what to do. Our landline number is ********** 693. Its so depressing being handled in this morning. Taking our money in this way is *****ing.