My dock disappeared

Hello, wondering if anyone can catch something I can’t. I created a dock image on a page https://www.thedeathdefeaters.com it is supposed to run across the top where you see follow on twitter and facebook. It was working fine till a few days ago. Other users post so I am not sure if anything they posted conflicted? but I even went and removed posts and it wouldnt come back? It is calling this image
https://www.thedeathdefeaters.com/wp-content/themes/side-blog/images/dock-bg.png
it loads here but not when it calls it? Does anyone know why I might not be getting this to show any more?

Thanks