1. Back up all your important data like photos, videos, contacts, messages, etc. on an online storage account, SD card or computer.
  2. Go to the settings of your Oppo smartphone by tapping the “Settings” icon in the app drawer or on the home screen.
  3. Scroll down the list of settings and select "Backup and reset".
  4. Select “Factory data reset” or “Restore factory settings”.
  5. Confirm the action by tapping “Reset phone” or “Erase everything”.
  6. Wait for the reset process to complete. This may take several minutes, depending on the amount of data stored on your smartphone.
  7. Once the reset is complete, follow the on-screen instructions to set up your Oppo smartphone as a new phone.

Note that factory reset will delete all data, apps and files stored on your Oppo smartphone. Therefore, it is important to backup all important data before performing the reset.