problem to load preview images on post

Hi everyone, I have a problem on my site, in the part of the gallery where all the pictures are just a few pictures appear as “preview” pictures, on the others there is only “alt text”, no pictures. But when i click on that “alt text” the image appears normal. Can anyone tell me what is the problem and help me with this problem? I use the “Lazy Load by WP Rocket” plugin, if I turn it off it’s the same problem. Problem image LINK.

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