Sony Xperia Z3 back cover is lifting up itself!!!

[Sophiania]

I bought the Z3 for about a week. Today i felt like that my finger slipped from the edge of the glass when touched the back cover. So i checked the back cover and found the top side and left side are above the midframe. I nearly believed it just should be. When i tried to press the edge of the back cover, i noticed it came down a little, and when i let go, it went up again. Though it's a tiny move, i really saw that very clearly. Why it happened? Overheat motherboard? Do you have the same problem? And if the phone still waterptoof?

 

[JBeef]

That doesn't look right. You could test if it's waterproof. To check it you have to close all flaps and call *#*#7378423#*#*, then go to service test and pressure sensor. With all flaps closed press gently on the screen, if pressure will increase that means the Phone is probably still waterproof (although I can't guarantee).