Mobile Site Character Anomalies in Paragraph

Part of the problem I am having is that I really don’t even know how to troubleshoot for mobile browsers.

I’m using the plugin WP Mobile Detector to switch out themes on standard and mobile browsers. If you’ll take a look at the site, blackbirdcoffee.co, you’ll probably see, as I did, quite a few of these a€”. There are plenty more on the site’s other pages. This creates a pretty significant readability issues. Again I don’t know where these are coming from and I don’t really know where to begin. Any help or suggestions would be greatly appreciated.

Thanks,
Sam