this happens when the spokes on one side of the hub are not relating properly to the spokes on the other. Its tough to see if you are new at this. you need to drop one spoke into the hub and look how that hole relates to a hole on the other side of the hub. these two holes and their spokes need to relate to where they connect to the wheel. if the first spoke is just slightly ahead of the spoke on the opposite side it will end up in a hole on the rim one spoke hole in front of it counter mate from the other side of the hub. you could still have problems but this is the most common oversite and the one that mostly caused your problem