Can't import texture for new swatch on a CC object recolor

I'm extremely new to Sims 4 Studio but I found it really straightforward and easy to use for adding swatches for hair and accessory recolors. Now I'm attempting to add some more color options in the form of additional swatches on a CC couch, but the Import Texture button is greyed out.

ibb.co/C96jZsp

I apologize if this is a common issue, I checked the help threads and couldn't find this exact problem.

Thank you!