Does not Work for me

I created a parallax scroll option for a page,got the shortcode and added it to the page. Then I found out I needed to change the background image, and so I did. It still does not work. All that can be seen is the shortcode under my thumbnail.

This is where I tried to add parallax scroll: https://alllivesaresacred.com/share-prolife-stories

My current theme is Optimizer PRO.