Hard to contact

On the 11th of March I received my mtn statement, I wanted to cancel some part of my contract that i was no longer using, sent a mail to info@mtn.... Up until today i did not hear back from them. Yesterday i called the number for contract customers from the phone in question. I could not get through, it just disconnects immediately. I then phoned 173 and waited to speak to a consult for more than 30 min. only to give her the reason for my call and then she said she was going to put me through to the contract dept. Immediately the call was disconnected.I again tried the 808 number from another phone and could still not get through. How do we contact this service provider when we cant even get through to the. I suppose the next step will be to go to a mtn store and by the time i get to the store they will have charged me for a service that i have not being using.