My guy charge you phone up to 100% and
Try the following
- Press volume up and power at the same time a green droid with exclamation mark should appear navigate to wipe data using the volume keys if it fails try option 2
- Simultaneously press volume down and volume up and power also there should be pop up with 2 option 1 recover mode and 2 factory mode mode
- Use the volume up to chose recovery mode and like l said a paranoid green android lying down will appear now quickly navigate to wipe user data.
If a hard reset does not help then this here: http://www.satechhelp.co.za/11952/Flash-Download-Mobicel-Onyx-Firmware-Rom should work for you