OG image not working/overriding on shop page

I set the Social Meta plugin on a ecommerce site and all single products shows correctly the product image, the posts/homepage too.

I selected to show the main image and when the image is not present, I’ve set to use a predefinied image.

On the shop homepage https://www.ferramentadiomedi.com/shop-categorie/ it shows one of the images in the page content, and ignores the predefinied image AND the the main image I’ve set.

I tried to override the Meta Social settings too, but it doesn’t works. In the fb debugger it always chooses one of the category images, not the one I’ve set.
Any suggestions?