Kicad 9, Mouse Bites, and Freerouting

Previous messages were resolved. I recently added “Mouse Bites” to my layout. I have eight small (DIfferent) boards to combine into one board. The Addition and board “Cut” are in, and DRC has no errors. I had to move a few items, nothing drastic.
I tried to use Freerouting with the new board, and it produced the error:
“Multiple footprints have the same reference designator ‘mouse-bite-2.54mm-slot’.” I downloaded the footprint from GitHub…
Should I edit each “mouse” and assign a “reference” or place a ‘~’ there?
I’ve enjoyed (and dreaded) the learning curve so far and am getting ready to order my first board>

Freerouting is a Plugin and not part of KiCad . . . but the error message tells you all you need to know . . .

So your mouse bite footprints all have the same reference designator, they need to be unique so you need to change them.