Every time I open any app then press the home button to get out of it: meaning that the app is running in the background, then press the home button again to swipe away or close the app the message, "unfortunately the process com android systemui has stopped" , appears and I get sent to lock screen. I haven't done anything to my phone before this message kept appearing. I didn't touch any files, download games, or do anything risky to the phone. Is there a way to fix it? If there is please help.