Problem with Single Product being Recognized at Variable

I have a WooCommerce shop, and I’m trying to show the “Add to Cart” button on category pages. I’ve done so, but now I see the buttons read “Select Options” even though there are no options for the products….

I’m not sure why WooCommerce thinks this is a Variable product when it is a Simple product with no options.

https://sophinailpolish.com/product-category/nail-polish/

*Also, some of the buttons read “Add to Cart” but when I update that product, like changing the text in description, the button then changes to “Select Options” rather than “Add to Cart”.

Is this a bug?? Or how/where can I look to fix this??