Unsatisfactory ,Poor ,Rude Service

returned a Duracell charger that wasn't working at the MTN shop L156 ENTRANCE 1 SOUTH GATE MALL, I was given attitude and told if i didn't know the policies of returns because i didn't have the cover it came in with, another employee Kamohelo went to make a call at the back office ,after a period of time he came back told me it was okay to exchange the charger but he can only do it on Saturday15th Oct but he will call me first .I never received the call from him. I decided to call the shop spoke to Kamohelo he admitted he forgot to call me ,i said to him the service provided is bad and travelling back and forth to the shop is costly and now again i'm the one using my airtime to call since he did not , his reply was that he was only doing me a favor by agreeing to the exchange since his regional manager told him not to do it , i then asked for the regional manager's contacts which he gave after telling me he can't assist me today because they busy with stock count/taking .I called the number provided but got no reply .