Confirm feature availability
Trash cleanup may not be available in every edition.
Check Full Disk Access
Some Trash locations are protected and can appear empty without Full Disk Access. Enable it for the active copy, quit and reopen diCleaner, then rescan.
Check Home access
The App Store edition may also need Home Folder Access for supported user locations.
Check the volume
External disks maintain separate Trash data. Connect and unlock the volume, then scan while it remains mounted.
Confirm current contents
Finder or macOS may already have emptied Trash, and another user’s Trash is not the same scope.
Do not create throwaway important files merely to test. Use a noncritical test item and restore it before emptying.