Thumbnail link not opening file

I am having the same problem. I have created 3 galleries. One works perfectly, the other two, not so much. I have tried using both Template 1 and 2, and having them open in a lightbox and separate page. No matter what the one gallery works, and the other two do not.

This is the working gallery:
https://www.premoindustrial.com/wppg_photogallery/gallery2/

This is one of the not working galleries:
https://www.premoindustrial.com/wppg_photogallery/gallery4/

I’ve deleted and recreated both non working galleries with no change, still not working.

Any ideas what I am doing wrong or if it’s a glitch?

Oh, I will be creating several more galleries like this, so I’d love to know how to fix it!

Are you using the watermark feature by any chance? When I go to your gallery 4 page, it gives me a 404 error. Why did you ask this same question using a 1 star rating?

I am not using the watermark feature.
I didn’t rate anything or ask the question again so I am not sure what you are talking about there.

These are the galleries that aren’t working:

https://www.premoindustrial.com/wppg_photogallery/gallery6/

https://www.premoindustrial.com/wppg_photogallery/gallery7/

I tried to delete and re-upload pics once more, but it’s still not working.