Gallery Attachment page don’t links to the full-size image

I try to get answers in how to click on the thumbnails from the gallery and open the image in a new page with a full size… I found many people with the same problem but i didnt find any solution.. There is a solution for this problem?

https://www.yvymag.com/2010/01/harry-wakefield-takahiro-ogawa-metal/

If you click you will see that the images open with medium size…

Marcello