MTN Worst Customer Service

When you take out a new contract with MTN you get world class service, When you query the result of over charging for the same contract you get the world worse service... I have logged calls I have email an agent that is now ignoring my emails and i am still no further to know why I am being over charged and why I am allocated less data. The only thing the customer care mailbox does is say that someone will assist but no one calls ...Agent don't call back either and they do not respond to emails Ticket # 1 *** Ticket ***