False Advertising - Disgusted with Sony

I have recently got a Sony Z3. The phone was said to be IP68 rated which meant I could use it under water within certain limits. On a small holiday when I could actually try it the screen got a hair line crack as well as the phone did not switch back on. All the ports were closed as my cover used with the phoned sealed them and the charging point is always closed if it's not charging as this would be annoying to work with if it wasn't. MTN suggested I take the phone to Sony's repair centre SSS cellular. After a few days I receive a mail saying my phone is water damage and that the phone will not be covered under warranty and is beyond economical repair. I have tried to explain to Sony the problem and all they say is their decision is based on SSS Cellulars outcome. So my understanding is that Sony is all ears when you ready to buy but when there's a problem you routed somewhere else. So basically Sony is selling a phone they say use under water and when it breaks they will not cover you as well as not provide you any more information besides we will not cover you!!! (Doesn't sound legal). Please Google these problems to see this is a issue through the world.