Sony Xperia Z3 malfunction

How is it that my Girlfriend has a waterproof sony Xperia Z3 and it get submerged for about 30 seconds and it stops working. All the seals were closed tight, and the phone is flawless, no damage to screen or body as its been in a protective cover all its life, of about 4 months.<br> So it gets taken in and we have to pay to get it repaired. Lets not forget all the adverts about Sony's underwater store and underwater photoshoots etc, where they boast on how waterproof the phone is. if you youtube sony xperia Z3 you see all fantastic underwater bragging, which seems to me to be simply misleading advertising if Sony takes no responsibility for their phones waterproof functionality malfunctioning.<br> <br> This is a handset malfunction, as it was performing the task that Sony advertises as being the handset's best feature. So why is it that we have to pay to repair an under warranty handset that malfunctioned during standard advertised use. Its also the first time it was ever submerged, so the claim of chlorine, wear & tear etc cannot be used.<br> <br> Please sort this out.<br> <br> Please contact me on email [Email Removed]