Lightbox Not Working on Mobile

Hi. I have the premium version of the plugin running on my site. On the desktop it is working great and functioning just as it should:

However, on my mobile device, the lightbox is not working. I have tried the Safari and Chrome browser on an iPhone 7 and the gallery loads and displays fine. However if you try to tap on an image, the light box does not open, and nothing happens:

https://runningriddles.com/races/marathon/the-2017-run-for-the-ranch-marathon-in-springfield-missouri/

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