Recently some of our customers forgot to put their user ID in consignee's information. This will make it hard to identify which user the parcel belongs to, so it is appreciated that the user ID is input.
Our system can not detect a parcel only with your nickname/true name, what matters is always your user ID.
Especially some of the Japanese online stores will only provide flat rate ship. There would not be waybill number on flat rate ship usually. For parcels without user ID and waybill number, it is extremely slow during operation.
So you will have a much better user experience when you add your user ID in your consignee name and/or consignee address.