Telkom hopeless

Telkom really sucks, been trying for months to cancel my father inlaws telkom account. He is a pensioner and we have been covering the bill. The problem is that the landline and wifi is constantly down, havent really made use of it in the last 2 months. We went to on numerous occasions to cancel, filled out the necessary form even got a call back, but still not cancelled, that was 6 months ago. The service really disgusting.