Selection does not show

Hello,

I have some problems showing selected products from the filter. For example: https://www.fietswaar.nl/product-category/kleding-en-bescherming/helmen/helmen-helmen/?14_attribute=34932

and: https://www.fietswaar.nl/product-category/accessoires/sloten/kabelsloten/?_attribute=31982

The products of the selection do exist and are in stock, for example: https://www.fietswaar.nl/product/litelok-kabelslot-go-flexi-o-85-art2/

and: https://www.fietswaar.nl/product/abus-helm-pedelec-2-0-ace-glacier-blue-s-51-55-cm/

Other filter selections do work, like: https://www.fietswaar.nl/product-category/accessoires/sloten/kabelsloten/?10_attribute=4074

I have tried the following:

Go to WooCommerce > Status > Tools from WordPress admin. At the bottom, there is a section called Regenerate the product attributes lookup table. Click on the Regenerate button on that section.

and:

I have tried to show the selected products with the Twenty Twenty-Two theme, unfortunately with the same results.

Would someone be able to tell what is going wrong here?

Thank you in advance!

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