Here's a trick to help you delete spans of bands that show as used or lost and are not used or lost. .
1. Go to "utilities-table designer-copy" and copy your file structure to a new file named "trash".
2. Go to "file-append" (still under utilities). You will be prompted for where to get data (your working file) and where to send it (trash). Then you will be asked if you want to use a filter. The answer is YES.
3. Select the spans using the filter, append them to trash.
4. Go to "file" and choose "delete" and delete trash. Choose the option 'delete--mark as unused--no file".
The bands should be in your inventory and marked as unused.