Empty Hook Report
The Empty Hook Report will display a current list of hooks that are supposed to be empty.
If a key was returned to an incorrect location, it is often located on a hook that should not have a key, which would include all the hooks listed on this report.
The last unit assigned to the hook is historical information. This is effectively a list of unit keys that are currently out of your system. If any of these keys are actually in the cabinet, they should be removed and rescanned properly to register as back in the system.