Unimpressed with Vodacom repairs

I REALLY didn't want to do this, but frustration levels are now at a boiling point. I have an Xperia M2 Aqua which I got from Vodacare in April 2015. The problem is that my phone will just switch off and won't switch back on again. The phone has been charged each of the 4 times this has happened.<br> When it happens, the phone also doesn't respond to being plugged into any charger.<br> The first 2 times it happened, I took it to 1Two 1 Cellular in Craighall Park. They were no help at all.<br> The 3rd time it happened on 10 June and I took my phone to the Vodacom Repairs Sandton. When I gave it to the guy behind the desk, he said that I'm the 3rd person that week to bring in the same phone with the same problem. When I got my phone back on 19 June, the report was: 'No trouble found'.<br> 2 weeks later, the exact same thing happens. I took my phone to Vodacom Repairs Sandton again on 30 June and my phone was sent to the Repairs Centre AGAIN. When I went to collect my phone on 7 July, the report was: Part replaced, Software Upgrade, Part Reassembled, BC Adhesive 1 BATT COV-D, Adjustment<br> At least this time there was some type of report. But today it happened again. I would like a solution ASAP!