It is so easy to make a wrong cut when working with two-layered appliques. It happens to all of us. You are so accustomed to cutting fabric away that, before you know it, you cut too much.
I did that recently when working with an applique that featured two layers of fabric. The top one was cut away, like the center of a flower, and the outside was scalloped, like flower petals. Two layers were placed in the hoop before starting to embroider. After clipping the middle fabric to the placement lines, I cut the outside (petal) fabric by mistake.
Not wanting to pitch the project thus far, I took a deep breath and calmly thought of a solution. It was a sort of reverse applique.