Water damage Experia Z3

I have a Sony experia z3 that is 9 days old. I'm furious about my phone. I tested the phone in the water because it is a waterproof phone with the highest waterproof rating according to sony. Before presenting the phone to water I made sure and dubble checked all ports was closed. The phone just went dead. I took it back to vodacom and they said its not there problem. Sony is using false advertising and they are not responsible for what happened. They say I have to take it up with sony. I want someone that will assist me. Because jumping from one pillar to another is frustrating. And I want answers. Vodacom keep on saying they Will sort it out with sony and will keep me up to date. Its nearly been a month and no one keeps me up to date. And every time I go to vodacom the just say they did not hear anything from sony. No one can give me answers and I want answers. So either sony is *********** or vodacom is ***********. I would appreciate if someone will contact me in this regard.