stinking attitude with very little response

im really disappointed in the service i recieved i have a contract with them and in 3 months of my contract the phone gave me problems which i took to samsung nandi drive because of the waiting time they replaced my whole main board which i was not happy with 2 weeks after i sent my phone back in seen has that i couldnt answer calls. the phone still gave me troubles i sent it to the branch they had my phone for 3 months because somebody forgot to book my phone in. i requested for a new device which they refused to do. i was then promised a loan unit which up till date didnt recieve my phone is still at the branch and i still didnt get any contact from them when they promiosed to give me a call 2 days after was booked in. i still have not recieved a call. really where does all this end im quiet sick and tired and really fraustrated with the management team at telkom mobile. what can be done? as i no longer want this device.