Not working on mobile

Hi,
On desktop the images open nicely in the lightbox, but on mobile the images open up in a new link. Any ideas why it’s doing this?

In the link I supplied, ignore the first images, as this is generated through a Divi template (and works as it should because it is using the Divi Builder). The images below it are stand-alone images in the post content and are not displaying / opening correctly on mobile.

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