Excel button greyed out

The Box file "Larson Jumpstart Resource Engagement 02-12-2026.xlsx" is locked. The Unlock option appears in Box but is disabled for me, even though I am a co-owner of the folder. Please identify the lock owner or checkout owner and remove the lock so collaborators can edit the workbook. The icon at the top of the folder shows that the file above is being edited with BOX for Microsoft 365. I have multiple users inputting information in this same file and they need access to it. Any assistance would be helpful.