To reset your device, turn off your display and hold down all three buttons on the front and power it back on at the same time while pressing down on all three buttons.
Display will read [RESET DATA] press the 'MINUS' button for "no" and 'PLUS' button for "yes".

The display will then ask if you wish to [RESET DEVICE]  - you will then need to again press the 'MINUS' button for "no" and 'PLUS' button for "yes".

Select as appropriate and your device will reset - this will be completed once your device shows the time.

You can also view the process on our video below: