There is a known error related to the Special Nendoroid 2000 Celebration Base bonus item. This bonus item will only be provided to the items listed at the below link, and only 1 per Nendoroid pre-ordered:
https://www.goodsmileus.com/featured/Nendoroid-2000
It is possible that your order confirmation will reflect an extra quantity of the Special Nendoroid 2000 Celebration Base beyond the number of figures you ordered from the list in the above link. Unfortunately, this is an error in the order confirmation system and should be disregarded. You will only receive 1 Special Nendoroid 2000 Celebration Base bonus item per Nendoroid pre-ordered from the list in the above link. We apologize for any confusion that this error has caused you.
If you have any questions or concerns about your Pre-Order, please do not hesitate to reach out to us by submitting a support ticket here: https://help.goodsmileus.com/support/home . When you submit a ticket, make sure you include your Order Number so that we can check the status of your order. You may also contact us via phone at 213.460.1167 between the hours of 9am-5pm PST, Monday - Friday.
We appreciate your understanding and patience with this situation!