Last image in gallery – wrong order

I’ve set order to be “by filename” and “asc” and everything is ok, but the last image shown should not be last, but few images before last.

interesting, when I check on my laptop with different resolution, everthing is ok. On mobile phone it is ok in portrait layout, but when it is turned to landscape it is no good.

Is it a bug or something?

I tried reinstalling plugin, upload new images, rename images, clear cache but nothing helps

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