Header placement

Wow, thank you so much for your quick response! I asked this question on another forum, maybe you can help me because it goes along with this. https://wordpress.org/support/topic/header-does-not-show-up-in-mobile?replies=1
I added my header image through the Appearance > Header option and it shows up through desktop, not mobile. I’m new at this stuff so it doesn’t really make sense. Maybe I have to do a bit of coding to add the image in? If so, do you know where? I can’t seem to find he answers anywhere.
Thanks so much!
Jessica

That is what I did. I uploaded the logo image and it shows up on desktop but not mobile.