There are myriad reasons as to why it might not be working, try the basic, if the phone has any type of case, film, glass, remove it, and try again, if not, then do elaborate as much as possible.
I tried everything.. Ready....even i repair in computer... Stil my power key f#$ked Cnt use... Wht else I must do... I nvr been think to change phone.. Dnt make me do tht... Pls I'm using Sony.. Since 6 year... 3 xperia...
