Slide-in not working properly on mobile

Hello, we successfully installed and setup a slide-in CTA using Hustle which shows nicely on desktop, however on mobile phones it does not work. Instead of sliding in when the visitor reaches 60% of the page, when the visitor his 60% he is taken to the very bottom of the page where a completely unstyled slide-in is hanging out below the footer, crammed under the copyright. We tested on a least two different Android phones and it’s the same issue. What is causing this and how can we solve this problem? Thank you.

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