Unprofessional services

This is with so much anger / disappointment! I took out a contract phone (4 months ago) it recently gave charging problems. I took it in to MTN SOMERSET MALL to be send for technical support and the lady assured me they send it off for repairs, only to find out they never couriered the phone but they did couriered another phone. Now the lady i spoke to is avoiding my calls cause she knows they messed up.