Why has my phone reset all ringtones wallpapers and settings

[AC Question]

I woke up this morning late for work as my alarm on my s7 edge did not go off like it has done every morning since I got it. I look at my phone and my wallpaper on the lock screen is a default one and all my ringtones and certain settings have been reset to default like screen inactivity time out screen brightness and things like that any ideas?

 

[B. Diddy]

Welcome to Android Central! But all apps are still installed, and you haven't lost any data? Does it come back if you reboot?