Xperia z hanged+frozen screen.

[mascox14]

My sister's xperia z isn't working.
was working fine suddenly stopped working.
hanging,screen not responding
i'll post the link to the video*
and she checked the charging lid and the color was white.
please tell me a fix to this.
""somehow i cannot add link to this thread so please search "MASCOX14" on youtube and it's the first video you will find in my channel "VID 20150727 WA0002"
sorry im kinda noob..
please help

 

[Pyramid Head]

My sister's xperia z isn't working.
was working fine suddenly stopped working.
hanging,screen not responding
i'll post the link to the video*
and she checked the charging lid and the color was white.
please tell me a fix to this.
""somehow i cannot add link to this thread so please search "MASCOX14" on youtube and it's the first video you will find in my channel "VID 20150727 WA0002"
sorry im kinda noob..
please help

it seems like a screen malfunction i suggest you get it serviced
there are some things you could try
-pc companion repair
-flash another ftf(try at your own risk) http://xperiafirmware.com/8-firmware/33-sony-xperia-z-c6603