xperia z ultra Touch screen problem

[alinarif]

My Sony xperia z ultra screen does not working. After pressing power button touch works. But after unlocking lock screen touch works rarely or not working. Please help me to give a solution

[Phy]

boot on safe mode and check if you experience the same issue

How to boot on safe mode.
http://talk.sonymobile.com/t5/FAQ/How-to-boot-your-phone-into-safe-mode/m-p/348008#U348008

[Phy]

You can test the screen

1. settings
2. about phone 
3. Diagnostic
4. test 

or you can repair the phone with Sony PC Companion

http://support.sonymobile.com/gb/tools/pc-companion/

[MahmoudAtia]

I have the same problem on my phone Xperia zr 😕

[SophiaW]

Hi alinarif & MahmoudAtia, welcome to the community!

Follow Phy's advice and see whether the issue is or is not present in Safe Mode. If it isn't then just try clearing the data for third party apps installed on your device and/or deleting any of the apps you don't use/need. If the issue is present in Safe Mode then I advise doing a software repair on your handset using either PC Companion or Bridge for Mac.