Billing department bad service

I am being charged duplicates amount, my number is suspended, I made numerous calls, no one is willing to assist and rectify their system error, my number is currently suspended, its been a month now being taken from pillar to post, I am expected to pay the amount that is due even if I am disputing the amount, bad service, I have been with mtn for 15yrs now I have never experienced bad service. I wil never used Mtn service again, moving to another network