I recommend restoring your device, setting it up as new, and then slowly adding your apps back in. If you're still having problems it might be hardware related. In that case, take your device into an Apple Store or contact [URL="https://forums.imore.com/e?link=https%3A%2F%2Fapple.sjv.io%2Fc%2F221109%2F473657%2F7613%3FsubId1%3DUUimUvbUpU2781457%26subId2%3Dvbim%26u%3Dhttps%253A%252F%252Fwww.apple.com%252Fsupport%26ourl%3Dhttp%253A%252F%252Fwww.apple.com%252Fsupport%253Fafid%253Dp239%25257C159229%2526cid%253Daos-us-aff-ir%2526subId1%253DUUimUvbUpU2781457%2526subId2%253Dvbim%2522&token=sXIyP1i8]Apple Support[/URL].