New Window Error…

I installed the plugin, and then added the external link to the product we sell on Amazon. However, when I tested it by adding the product variation with the link, it: 1) opens a new window but instead of going the actual product page on Amazon, it produces a page on our site with a 404 error with the original product’s link and then the new link right after it in the address bar. 2) It also replaces the Favicon on the original page with a favicon from Amazon.

Any ideas why or how to fix this?