Lego 42134 (Megalodon Monster Truck) pull back not working?

My nephew has built this set but when you do the pullback to make it charge up to be able to drive itself forward, it just clicks a couple times and doesn’t go anywhere? I mostly do classic Lego and don’t build a lot of technic things so am not really sure how to help them beyond saying to take it apart and be sure gears are aligned and the “motor” piece has all its pins and is oriented the right way. Has anyone run into this issue or similar with other sets? Thank you! submitted by ...