Terrible customer service

Early in june i upgraded my handset to the samsung s6 , a few days later i experienced a major problem with the handset and therefore did not want it repaired or replaced , i wanted a different device so that i would not experience this problem again because i have wasted alot of my time , money and fuel running back and forth trying to migrate my contract , the sales rep and store manager was disgustingly unhelpful , i really considering a contract buy out that was offered by cell c , mtn customer service is **** , i suggest you fire the staff as they said they literally will not assist me and also **** to me and did not explain the terms of the contract properly not only that a few weeks later the handset price decreased and the sales rep was suppose to tell me that before i took the device. it is a defective device i read in my contract that i have a right to return it why didnt the sales rep tell me this , they are trying to keep their commission even though their customer service is ****