OK.
I hate to say this, but, when I said …
You missed this part.
Rainbow Unicorn FINAL.3mf (3.8 MB)
This is your second plate, the one with the issue.
To make it easier for you to understand what you need to do, I renamed the 5 coloured hearts as “heart” in the layers list and then dragged them to the bottom so they are rendered at the bottom.
This is how you have them printed first and other items above them.
