MTN - Worst Service "I will lose my job if I call my manager"

The worst customer service I have experienced MTN. I am trying to do a simple upgrade - I get transferred 4 times. When I ask for a manager I get told that they are in a meeting and that if they are disturbed they will fire the advisor! If this is how people are treated no wonder the service is so poor. The staff have very little knowledge and nobody really wants to help. I have been a customer for over 13 years but will now be looking to take my business elsewhere