If you click the start button on the chipper and you don't feel or hear a click of the button, then this typically means that the chipper isn't receiving power.
Check the fuses on the device and the mains power supply, including any extension cables.
Ensure that the bolt on the hopper is tightly secured. This is vital as the bolt acts as a safety feature for the wood chipper so it must be tightly nipped in order for the chipper to start.