MTN Worse mobile network

The worse mobile network in South Africa they billed me incorrectly from April to date in 2019 they make u do the work to try to get thru to mtn direct and get a contract so they can fix what they messed up and I have been put from pillar to post over a month and no help yet.... You wait 15 - 20mins just to get thru and then there is never supervisors or managers ever