The slider does not work at all on some pages, but works perfectly on others?

I have the slider on multiple pages throughout my website, but on some pages it works, at on some pages it doesn't. I have even duplicated a page, where it works, and then it does not work on the duplicate. I cannot figure it out.
On the pages, where it does not work, the product fills the whole page, at they are just listed downwards the page.