blue flag at beginning and end of piece

I don’t understand why a blue triangle flag has appeared at the beginning and end of my piece. I can’t find anything about it in the handbook and I can’t delete it. I lost all my edits to my piece when it did not save the changes, and I wonder if it’s related to this flag. When I tried to save changes, it said I didn’t have permission. We tried saving it with “Save As”, but though it seemed to work, I lost everything.
I hadn’t worked on these songs in years and had some problems with some kind of corruption overall, so I was going to copy and paste the song into a new document, but the clean document has the blue flag also. (AUGH) Thanks for any help you can give.