Appaling service

I bought my brother a R900 ps4 controller on 28th Nov 2014 only for it to stop working beginning of March where he promptly returned the controller (the unit being 2 months old)to the Bayside store where it was purchased and told it needed to be sent away for repairs. On the 20th he got a sms saying it was ready for collection only to arrive at the store and be told the service center sent back an empty box- went back to Game on the 24th March to collect his unit and was astounded to discover that it was CLEARLY not his and nowhere near being 2 months old. I was furious and returned the unit to the store on the 25th March where no one seemed to be able to help- poor Ntombi from CCare was phoning everyone who was anyone for help to no avail and the manager had already gone home. I left the unit there as we refuse to accept what is clearly someone else's old repaired and well used controller. Despite being told someone would call me the next day- we have heard nothing to date. If our controller has been misplaced somewhere between your service center and the Game branch, that's fine- replace it or refund our money as this is completely unacceptable. That controller was EXPENSIVE.