Force video on mobile homepage

Hi, I would like to force autoplay video on a mobile homepage (It's a very small video file, less than 9mb hosted on Vimeo.com) 

I had it all set up adding the video to index for homepage and it was working great autoplaying when I tested on mobile. Now all of a sudden the video has disappeared and reverted to a white background color on mobile. 

Is there anyway to add script that forces the autoplay mobile video 

You cannot force a video to play. Mobile browsers do now support background videos, but depending on the device being used, the connection speed and the browser version, the video may not load for every visitor.

You can set a mobile fallback image to appear when the banner video can't load. This will be better than the white background. For more details, see https://support.squarespace.com/hc/en-us/articles/218562738-Adding-background-videos#toc-step-5---add-a-mobile-fallback-image