Backup Exec 2012 - Disk Space not reflecting free space correctly

Greetings,

I started to run low on free space on one of my media servers so I started to delete a few 1-2 TB's backup sets for future backups. After I delete these sets, the stoarge does not reflect the amount I deleted. It is as if I did not delete the backup set. Besides picking the backup set and deleting it, is there something I need to do to free up that disk space?

Thanks,

Robert