incorrectly billed

i have been battling with Telkom for the past 5 months,being sent from pillar to post just to resolve an incorrect bill issue. i have been billed for a service that has not been rendered yet; its been an ongoing battle with the service provider for quiet sometime now I'm tired of being sent from pillar to post;wasting my personal voice minutes( been placed on hold on numerous occasions). disappointing/disgusting service ,