Workforce Mobile Version will not Update Thumbnail

[HannahSchaefer1]

I am trying to help our field team differentiate multiple Workforce projects by changing the thumbnail for each. The image will update in the web version, but is not updating in the mobile version. I've tried closing it out, reloading, refreshing, etc. but the default thumbnail continues to show up from a mobile device. Here is what appears in the web version:

And here are the same projects in the mobile version:

I didn't see any examples of this being an issue for others so I'm wondering if it's just a glitch? Any other ideas are welcome!

Thanks!