How Do I Open Rig Mapping After I've Closed It, It's Not Letting Me Edit The Rig Map

Hi, I'm going through the Adobe Animate Classroom In A Book Text Book. Right Now the rig map won't let me edit. It looks like I've missed a bone on both of the characaters. I'm not sure where for one of them because it looks like the character does not have as many bones as the rig map.

Anyway, I would like to edit the 2 characters again, but the rig map window will not let me edit and I don't know why. Also, when I select the bones and right click, I didn't see any opens to edit the rig map. Maybe, there is something there but I don't know what the click.