Gallery Thumbnail Images Not Showing Up

Site URL: https://www.artistsandbeyond.com/wesleytaylor

Hi forum!

So, the gallery grid block image thumbnails on my site have stopped showing up and I cannot figure out why. They don't disappear in the Squarespace editor, but are completely absent from the site itself -- I've tried multiple browsers and multiple devices. 

My site has different profiles. Scroll to the bottom and you'll see where it says "PHOTOS" and you can click them, the lightbox will appear, but the thumbnails are completely blank. 

I do have a lot of custom code on the site, so I fear that something else may have triggered the thumbnails to disappear but I cannot for the life of me figure it out. Novice here. 

Any help with this please?

artistsandbeyond.com/marytesta
artistsandbeyond.com/wesleytaylor
artistsandbeyond.com/dianadegarmo

Thanks so much!!