Can't delete old TimeMachine backup In terminal, trying to do the following:    

$ sudo tmutil delete /Volumes/BACKUP/Backups.backupdb/lappy/2014-11-02-005458/
Deleting: /Volumes/BACKUP/Backups.backupdb/lappy/2014-11-02-005458


I get the following error:

Error (-36) deleting: /Volumes/BACKUP/Backups.backupdb/lappy/2014-11-02-005458
Error (512) re-linking Latest for machine directory: /Volumes/BACKUP/Backups.backupdb/lappy
Total deleted: 8.0K


Is there another way I can delete old backup files to release disk space?

And Time Machine window shows
I had the same problem and found the solution at https://discussions.apple.com/thread/8597674:


  Add your Terminal app (i.e. Terminal.app or iTerm.app) to your list of apps for full disk access in Settings > Security &amp; Privacy > Privacy > Full Disk Access.