Can't make changes in my prefabs

I added a script to this enemy, but it won’t let me drag my Player prefab into the Skeleton Component.

Image: Link below

file:///var/folders/nn/hhnbm5nn2dv1_z88ml8787bh0000gn/T/TemporaryItems/NSIRD_screencaptureui_wPeleu/Screen%20Shot%202023-03-17%20at%2011.23.12%20PM.png

205657-screen-shot-2023-03-18-at-34908-pm.png