Frozen contact page and phone call

[Banky]

My contact page gives me a frozen state, won't be able to search for contacts. It gives a frozen phone page can't make phone calls.

[Phy]

do you encounter the same while on safe mode?

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

How to boot on safe mode on Lolipop
1. press and hold the power key
2. once you get the pop up menu 
3. press and hold "power off" 
4. Boot on safe mode should become available