Disappointed with the service I've been getting

Last week I complained about mtn not doing anything about my query even today I still haven't heard anything from them every time I enquire they tell me about sales team that they'll get back to me within 24-48 hours.. What is it that a person has to do to be taken serious by mtn why can't they respond quick like they do when offering us contracts. I swear the biggest mistake I ever did was to have contract with mtn.. What is Raymond Sifiso Ndlovu Dabengwa and Freedom Phuthuma Nhleko doing about everything, all the complaints, how it fails its people.. Mtn needs to start talking people serious