Share your experience!
I'm sorry to hear that, but this is a user based forum, you will have to handle this with your local Xperia Care
http://support.sonymobile.com/global-en/contactUs/
Was the phone dropped or has any cracked or physical damage?
I can only give you an opinion, like anyone else, but you can check the warranty here
http://support.sonymobile.com/global-en/xperiaz3/supportDocumentation/