Why is my iPhone 13 wallpaper in the right aspect ratio still getting extended?

I made custom wallpapers for myself that were in the right aspect ratio (9.75 x 21.1) for my iPhone 13 and they all work perfectly well except for 1. When I zoom out to have the entire background visible a fade is applied to the top of the picture and when I try to turn off the extended wallpaper the wallpaper zooms back in. I have checked a few times that this is the right wallpaper size and all my other wallpapers work correctly. I will attach a slightly edited version of the wallpaper to this post.

[Re-Titled by Moderator]