[Pay with a Like] Pay with a Like does not show Facebook buttons

Hi, I have tried all different configurations but in any case the Facebook like button will not show up on my posts via the Pay with a Like plugin. The other three social media like buttons will. Please advise how I can get this working or is there a bug?

If you go to the bottom of the home page the very last post "Rambunctious Ram Animyzm Birthday Cards" and click on it you will see the LinkedIn, Twitter and G+ like button but not Facebook although it is activated.

Thanks for looking into this.

Daniel