First, attempt to rebalance/calibrate the hoverboard:

Place the unit on a flat surface and center the two sides Press the power button and hold it down for three seconds The display lights on both sides should flash and the unit beep for five seconds indicating the unit is rebalanced and ready to use.

If that does not help:

Turn on the unit and press the power button six times in succession. Each press or tap of the button should be no longer than half a second and there should be no more than half a second delay between the taps. Restart the unit and check its functionality.

Should you continue to have an issue please try resetting the unit:

With the unit on, hold down the power button for 10 seconds It should beep loudly six times Turn it off and then restart it and see if it will function properly You may need to perform this reset several times but if after completing the steps above three times, it does not function properly, please let us know.