[wdfb_connect] shortcode not working

I used do_shortcode ( '[wdfb_connect]' ) in my php file, but the Facebook connect doesn't show up as a button. It just shows as plain text.. not even a link.

To see what I mean, go to: http://socal.premiereinflatables.com/shop/bounce-houses/bounce-n-double-dip-castle-20150620/

Click the bid button and then you'll get an error saying you need to log in. But the Facebook connect button doesn't show.