The folder cannot be found.

Hi ​@y-mikami, 

Welcome to Box Community, and we’re going to help locate your missing folder. 

If you have correctly followed the instructions in moving folders within Box.com it shouldn’t disappear like you mentioned. No worries, we will ensure to help you investigate and find out where the folder has gone into. 

To do so, I’m going to create a new ticket and a member from the Box Product Support team will reach out to you shortly. 

Thanks for posting, and we hope to sort this out soon!