We sometimes still see unaccepted, pending collaborations on the collaborator list even though 30 days have passed since the invitation was sent.
Root Cause
The invited user did not have a Box account at the time of invitation.
Before the initial 30-day pending period elapsed, the invitee created a Box account. A new 30-day acceptance countdown is applied starting from the time the account was created.
As a result, the unaccepted pending collaboration will remain longer than 30 days.
Resolution
Please wait another 30days.