Sony Experia Z3 not water proof

Sony experia Z3 advert is a lie. It shows a man diving into the water with his phone taking photos underwater. Same thing I did and now my phone is in for repairs as the screen went blank. All ports were sealed yet water got inside the phone. I wasn't even 1M under water. ITS now costing me R5000 to have it repaired. I bought the phone at MTN festival mall in Kempton park, I took it in on 22 Dec 2014. Its now 01 Feb 2015 and Im still waiting for my phone back. Why do I have to wait, why was a new one not issued. Why must I carry the R5000 bill. I am going to take this matter to the customer consumers act