Vodacom Repairs doesn't take responsibility

Vodacom Repairs Century City doesn't take responsibility for a phone that got damaged in their possession. According to them, if a phone breaks while in their possession, it isn't their fault because all electronic devices break. I had an Xperia z3 compact which I took on a contract because it was water resistant and had a 20,7 mega pixel camera. After receiving a broken device from vodacom repairs and sending it back. It was classified as an out of box failure and I was allowed to take a lg beat among 4 other phones of similar specifications. The managers supposedly tried their best to escalate the matter but nothing had changed in over a week, they didn't even contact me for a week. Now every time I look at that phone, it depresses me knowing I am paying for an xperia z3 compact and I am using an Lg beat. I cant even take out a picture without seeing distortion now. I am now stuck in the contract for the remainder of more than a year being ********** with a phone I hate.