This has a blue spot.(seal marker)
At first I thought it must be from a miss-click, so I tried to delete it, move the mouse get white circle with cross, then red circle with cross, click; nothing. Try again, nope.
As a test I placed a seal marker next to it, then I net a notification of my first tag, so I didn't create the original. I could delete the one I created, but still can't delete the original.