How can I display this SEO facebook comment after every post

Hi,
I have installed it and configure my secret key, APP ID following your instruction.

But there is no comment form after post. I will add manual code after post?

http://suabeptutainha.com/chuyen-sua-chua-cac-loai-bep-tu-uy-tin-tai-ha-noi/
thanks

https://wordpress.org/plugins/seo-facebook-comments/