billing issues not resolved

This year my account was over billed and I'm still over billed every month.the guy by the name of latimo who is the contact centre team leader had promised to follow up with the finance department.he promised that adjustments will be done and it will be done in a month.which means that my next bill will have an adjustment on ot..but to my surprise the stupid network provider hasn't changed anything..they stil ripping me off....i regret the day i signed up with this network..you have given me problems for days..im sick and tired pf this service provider.you cant even get hold of the cancellation department..i am ready to leave this stupid network..u run your business like a joke..im utterly disgusted by the way you treat your clients..all you care about is making money but you don't deliver the service.i hate mtn and i want the billing issue to be resolved