My screen flashes in black while using

[Mae97]

The screen just go black for a whole second while using...... what should i do?
Xperia z2

[SophiaW]

Hi Mae97, welcome to the community. 

Does the same thing occur while in Safe Mode?

To boot your phone in safe mode press the power key until the Power Off message appears > hold your finger on Power
Off for 2-3 seconds until 'Reboot to safe mode?' appears > tap OK. To exit Safe Mode just power the phone off & then on normally.