Let me start by saying I've tried a ton of different help forums and none of them have the same issue I have. I'm trying to change my head texture. When I pick the file and click upload, the site loads for a bit and then comes back with the same texture as before. However, when I try a different image than the one I want, it changes to that image. I've tried changing between png and jpg, I've tried adjusting the resolution, everything I can think of but I can't get just this 1 image that I want to be my head texture. If anyone can help me I'd greatly appreciate it.

have you tried downloading the image again? sometimes images can corrupt and become unusable

you could also upload the image to discord and copy the image link and that usually works for me (or use some external site like this and it does essentially the same thing)