Trying to Double Check Deleted Items, Check Shred Items, And Clear Cache and Reload. 

Hi there, 

Welcome to Box Community and glad to help! 

We have corrected your account storage on your account. To verify this, log in to box.com> Account Settings> Used Storage. 

Let us know in this forum if you'll get this issue again. https://support.box.com/hc/en-us/articles/360043695334-Storage-Usage-Or-File-Count-In-My-Account-Is-Incorrect

Thanks for posting! 

Same problem.

Hello, my box account is showing that I've used 50gb of my 50 gb of storage although I've deleted everything in it, and I even deleted the items in the trash. I've also waited a few days in case it takes a while for things to reset on their own. Could you please do a storage reset for me? Thank you.