Buttons were disabled by custom plugin which you use on site. I guess wholesale market plugin. You can ask author how to enable it. This is not 100%, you have many other plugins which can disable buttons on shop pages, disable one by one to find it
https://monosnap.com/file/OBa7a2RX9V4BmkONBHj17yVikbuKAT
You missed to attach admin access
I've a bug with add to cart button. The button doesn't appear on category page.
Additional Info
Link on page with issue (Optional): https://www.mypolishmarket.com/boutique/
Buttons were disabled by custom plugin which you use on site. I guess wholesale market plugin. You can ask author how to enable it. This is not 100%, you have many other plugins which can disable buttons on shop pages, disable one by one to find it