Post Preview not showing in Twitter & FB

All the posts, seems to take time to load in FB, but it does show up. In Twitter some posts seem to not work at all. This is what I see in Twitter:
https://static.livechatinc.com/8801096/P4Z4CJMYV5/ff438a258965cb70e68aaa22e823fe46/Screen%20Shot%202018-02-13%20at%201.22.41%20PM.png

Also, the /blog page doesn't seem to show up in FB, nor Twitter. Ran plugin conflict test but it didn't help. Please check the chat notes for more info.