Dead k850

I have a problem with my k850.
Last night when i was typing a sms, the screen went black. but the light on camera and pad eas on. when i try to restart it. the light on cam and pad goes on but the screen is still black.

when i try to update it with SEUS. i get a message that my phone could not be update.

what to do?

Bring your phone back to the place where you've bought it.
There's no other way except SEUS to repair your phone for free yet.

What about try FULLFLASH firmware over some paid programme?? (Davinci soft, Wotan client apod...)