Stars not visible when using shotcode

Hi,

I use [kkstarratings] shortcode on numerous subpages of my website but it suddenly stopped working.
What is more interesting, I see stars correctly, when I’m logged into my WordPress panel and preview my website. But I don’t see stars when I browse my website in incognito mode, not logged into my WP panel.
Do you have any idea why is that?

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