Flexslider not appearing

Hello, in my new website flexslider is not appearing.
PHP 7.2, latest WP version, can’t see any error in apache log.

Can you please help? I created the category “Featured” with “featured” slug, I even tried “Featured” and “Featured”, and “featured” and “featured”, but still no slider.
Obviously, both posts have a featured image.

It was set from the customizer option, but I can’t see any difference between “Flexslider” and “No slider” setting.

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