I have some item on hold in mailbox and it lost. Then, when i play rock paper scissor event the gift didnt come to my mailbox
Reward from rock paper scissor event is in web storage. You need to manually send to you mailbox.
Some rewards received in mailbox is limited, will expire - read the mail for more information.
1.)go website log in ->https://www.sea.playblackdesert.com/MyPage
2.) check your web storage.
Thanks for the info