Added plugin with overlay box and a link with automatically added to it

I added a plugin called “Ultimate Social Media Icons” that would add an overlay DIV to the page once a user scrolls to the bottom of any page. However when you click on the (x) to exit the overlay, you are taken to the privacy-policy. On closer inspection it seems the entire DIV, including some additional text and DIVs are all wrapped with a that leads to the privacy policy page.

You can test it on a page like this: https://scarf.boutique/acrylic/taymore-checked-scarf-by-ted-baker/
Scroll to the bottom, click on the (x) or anywhere inside the pop-up and see the problem.

I contacted the makers of the plugin and they insist that it’s a theme issue.

Help!