Mobile Header Not Updating

I have updated the header on my site with a new png picture. It loads and has updated fine on my mac or any other computer. However, the old header/picture still loads and shows on my phone. I have made sure to upload the picture under the “photo for mobile” section in my Header section, have selected “publish and save” as well. What am I missing or why wouldn’t it be loading the updated one on my phone? The old picture was even deleted completely. I have the Get Noticed theme.