More than 2 weeks being unable to make calls

I have been an MTN customer for more than 15 years and I have 2 numbers with them. I have not being able to make calls on my cellphone (I can make and receive WhattsApp calls, SMSes and can reveive calls) even through my account is in order. I sent them a direct message on twitter, called the 808 number several times and even went to the Sandton store twice and my problem is still not resolved. I even did a swim swap with no success. I was given all sorts of codes to cancel call baring and so on and told to switch the phone on and off but the problem is still with me. My number is ********** .