copied adjustment layer cannot be clipped to the layer below?

Folks: how do I clip a copied fill layer to a new layer? Screen shot attached.

Here's the story: I duplicated a fill layer because I wanted to apply the same color to another layer. When I duplicated the layers, the new fill layer is unable to be clipped to the layer below it, the button is grayed out. Probably operator error, but I want to learn. How do I clip the copied fill layer to the new layer below it?  

Mac OS 13.6.1, PS 25.1.0