image size on right slider

Hello, I would like to use the category and slider right facility. I have the images on slider right set to 640 x 426 pixels and this seemed ok. There are four inages. Howvever, I have added a new post and when this comes up on the slider, it is slightly disproportionate to the others, it does not look level. In addition, on the mobile view, one of the images is displaced.
the size of 642 x 426 seemed to work well. I cannot understand why one image of the same size is causing this issue

• This topic was modified 4 years, 5 months ago by anniebeau.

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