I think I found the issue. What I thought was an iPhone 8 was really an X because in this image, when you hit iOS 17.5, even if you had picked 8 Plus before, the Device Type automatically changes to X. Sadly, I am unable to change to a lower iOS version, therefore am unable to select an iPhone 8. Any thoughts?

Here was my error message: The dimensions of one or more screenshots are wrong. Learn More Screenshots dimensions should be: 1242 x 2208px or 2208 x 1242px

This is my image