Lightbox not working correct

Hi,
I try to put in the gallery with lightbox and installed easy fancy box and got the images to show up as popup but still they are also behind the page itself and also it’s not possible to navigate, so what’s wrong?

https://spanien-semesterbostad.se/semesterhus-spanien/

Thanks,
anweb

https://www.ads-software.com/plugins/shortcodes-ultimate/