/books shows Books Archive, not Books Grid

First, I usually roll my own set-up here, so I was pleased to see your plugin, thanks! But, the implication is that when I activate it /books will become a nice grid of books, right? But I’m getting the usual CPT books archive here, looks like a blog.

I inherited this site and this plugin was already installed and activated and I believe it was fine before, so I’m not sure what I’m missing. ??

Help? Thank you!

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