The LG Stylo 3 Plus has anti-theft and may affect how you are able to master reset the device.
- Sign out of any Gmail accounts assigned to the device
- Tap Settings.
- On the 'General' tab, tap Accounts & sync > Google.
- Tap the email account assigned to the device.
- Tap the Menu icon at the top right. You may need to remove the Pen Pop icon to see the Menu Icon.
- Tap Remove account.
- Tap REMOVE to confirm.