In order to hard reset a Motorola C390, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
Motorola C390 device will be brought back to the default configuration of a brand new device.
1. Turn on the phone. Enter Menu and then Settings, Advanced Settings and Reset Defaults.
2. Select Reset Settings.
3. Tap in your security code (by default it's 000000) and select Ok.
4. Yeah yeah, read the prompt and confirm the process by selecting Yes. Done. Hurray. I am so glad.