Terrible service from MTN SA

Went into Westgate shopping centre to do an upgrade. Chose the phone and which package I want and waited and waited. Was then told because I was on an older system I cannot get my upgrade. Was in the store for over an hour (what a waste of time). Was told by the MTN consultant that they are turning away customers because all people on the old system cannot upgrade because of the MTN system. The new upgrade options are not reflecting on the system. What's going on with MTN? Such a big company and have such bad system issues