2. This toy is intended to be used for outdoor. When the wheels are on a very smooth surface, it may not go smoothly. This design is to protect the safety of children and prevent them from walking too fast. PLEASE try to use it in a rough surface. If it still does not work, it may be the internal parts of the aircraft are misaligned during delivery. You can tighten the screws at the bottom to help the aircraft return to normal operation.