Factory reset will erase all files on your device, you'd better to back up the data in case of losing important infomation in advance. Google backup or MobiKin Assistant can help you make it easily.

Factory Reset

WARNING! When you factory reset the device, all of your personal data stored on the phone’s internal memory will be deleted, such as ringtones, media files, contacts, downloads etc. Furthermore all settings will be restored to factory values, but data located on the SD and SIM cards won’t be affected.

NOTE: Before your reset the device, you can check this thread for a guide on how to back up data, and this thread for instructions on restoring data.

Factory Reset via Settings:

1. Open “Settings”
2. Access “Cloud and accounts”
3. Tap “Backup and restore”
4. Optionally, turn “Back up my data” and “Restore” ON or OFF
5. Return to “Settings” and access “General Management”
6. Tap “Reset” > “Factory data reset” > “Reset”
7. If your phone is protected by a lock screen, enter your password/PIN to proceed
8. Tap “Delete all”

Factory Reset via Recovery:

NOTE: If your phone prevents you from resetting it via Settings, you can try resetting the phone via Android Recovery.

1. Turn the phone OFF
2. Press and hold “Power” “Volume Up” and the “Bixby” / “Home” buttons at the same time
3. From the Android screen, release the buttons and wait for access to Android Recovery
4. In Recovery, press “Volume down” repeatedly to navigate the menu and highlight “Wipe data / factory reset”
5. Press “Power” to select the highlighted option
6. Use the volume keys to highlight “yes – delete all user data” and press “Power”
7. Highlight “Reboot system now” and press “Power”

Reset Network Settings:

NOTE: When you reset network settings, all your saved Wi-Fi and Bluetooth connections will be deleted, while data restrictive settings, background sync settings, and network selection mode will be restored to factory values.

1. Open “Settings”
2. Go to “General Management”
3. Tap “Reset” > “Reset network settings”
4. If your device is protected by a lock screen, enter your password/PIN to proceed
5. Tap “Reset settings”