Response from LEGO SHOP
15 September 2020
Natasha, LEGO® Customer ServiceThat's no fun, a truck that won't move forwards! It does sound like something might be wrong with the build, so the best thing to do is to take that section apart and build it again. Pay close attention to the instructions, as even a small mistake can cause the model to not function properly. If you're sure everything was built correctly and you're still having trouble, or you notice any parts don't seem to be functioning properly, get in touch via LEGO.build/Service-BV and our experts will help you out.