See attached screenshot.
Your theme or one of your plugins is adding og tags to your source code.
og tags are open graph tags (See http://ogp.me/
for more info).
These tags are used by social sharing sites like Facebook.
The og tags display the wrong info (see below).
The og:title for example shows not the title of your product detail page.
The og:url for example shows the url of your home page and not the URL of the actual product page.
That's why the Easy Social Share Buttons plugin is not functioning properly.
You should get rid of these tags or make sure they are filled in correctly.