Restoring your device to default settings helps when the device crashes and resets itself or when apps freeze/hang or reset the device.
Performing these steps resets all system settings (e.g. ringtones, sound settings, display settings, etc.) back to their default values. Personal data, such as downloaded apps and media (pictures, videos, music), aren't affected.
From a Home screen, navigate: Apps icon > Settings > Backup & reset (Personal section).
Tap System settings reset.
Review the info then tap Reset system settings.
If presented, enter the current PIN, password, or pattern.
Review the info then tap Reset system settings to confirm.