If you have noticed that your slider is not responsive on mobile devices, then chances are you have either a “fallback image” inserted in page options, or you have a missing image in one of your sliders.
A fallback image is used to override the slider to show a single static image, and a missing image can prohibit some sliders from running correctly.
If a self-hosted or YouTube video is added to the Fusion Slide and the preview URL/fallback image is missing, the slide can also not show.
1. Make sure you do not have ANY missing images in the slider, all sublayers/backgrounds that have images must have correct URL’s.
2. Check for a fallback image inserted in the page options, it will override a responsive slider. See the image below for a visual representation.