Dear Ito san,
We are so sorry to making this mistake! We have checked our packing dept, and confirmed that is our staff put the last box contains with remaining pcs on the desk without any mark. The people who took over the work had mistaken as the full box, and put it in the carton.
From this time, we will pay more attention on this situation, regarding the last box contains with remaining pcs, we will mark a signal and open the lid!
Sorry again, and we should be more carefully.