Variation swatches not working with filters on Shop Page

I am using this plugin but the problem it works well on all pages but on Shop/Archive Page
when a filter is set swatch doesn;t get selected & image doesn;t change for product image

it doesn;t work on this https://theflagcorp.com/shop/product-category-country-flags/?product-category=car-bike,undefined,miniature

but work on https://theflagcorp.com/shop/

so the problem is with filtered products

any help is appreciated

The page I need help with: [log in to see the link]