Thank you for your reply Boddan.
The post that might worked for you while sharing on Facebook might be the ones that have photos specified through Yoast…
Try this one: http://waleg.com/celebrities/morgan-freeman-in-luxor-for-the-story-of-god/
I just did and it didn’t work.

Could the reason be the many lines of codes before the actual featured photo of the post and content?

I’m very grateful and satisfied with your theme and efforts invested in it, I’m just trying to help make it even better by reporting such issues.

Thank you very much again.