If your phone is not working properly, you can reset some settings to their original values.
- Back up the content you want to keep to a compatible memory card or to a compatible computer.
- End all calls and connections.
- Tap Settings > Reset phone.
- Type in the security code.
This does not affect documents or files stored on your phone.
After restoring the original settings, your phone switches off and then on again. This may take longer than usual.