Solution: Check that batteries are inserted with correct polarity.
Ensure that battery polarity matches symbols on inside of battery cover.
Solution: Replace batteries
Unscrew battery cover. Use thumb to slide cover out and lift up. Remove dead batteries. Replace with fresh batteries, observing correct polarity. Never mix old and new batteries. Replace cover and screw.
They say that this electric version could outrun the petrol one... the problem was, the designer never checked the batteries for size, and it was therefore never going to outrun the petrol one