Every time my A20e screen switches off (whether via screen timeout or power button) the phone crashes. To get it to successfully reboot, I have to press power and volume-down for a few seconds. Then I have to keep pressing the volume button to stop it crashing while the Samsung logos come up etc. Still if the screen switches off, it crashes. I removed most of the apps with no improvements and then performed a factory reset. Still no improvement. Is there anything I can do to fix this?