Job card no R393694

On 2014-10-21 the Samsung S3 was booked in at N1 city because of a total power failure. The phone had a small crack in one corner that happened two months before. About 1cm crack in the corner from side to side. This did not influence the view on the screen or the working condition of the phone. After about two months the phone just died and did not want to go on after that. We booked the phone in for the power failure. The quoted to fix the screen for R2500,00. It was explained to N1 city branch and the customer service that it was not the screen. The phone was not even six months old when this happened. This is obviously not due to the screen. Two of my friends has the same phone with more serious cracked screens and the phones still works. I feel they must repair the phone or replace it. When you buy a phone you do not expect it to last for less than six months. They cant even tell us what is wrong with the phone. All I know is that it is not the screen. I have been talking to numerous employers of Altech and the N1 city branch. I have send e-mails and reported them on Facebook. A new phone is not even R2500,00. I am one person talking to a lot of different people. Please help.