Not Displaying Image - Summary Card with Large Image

cards

#1

I’ve a blog named websiast.com ( www.websiast.com ). I’ve created Twitter Card (Summary Card with Large Image) it also got whitelisted. It shows up correctly in the card validator ( http://prntscr.com/8jwwcq ), but it is not showing images when tweeting using the share button below the blog post. My site is using wordpress and jetpack for showing share buttons. I’ve also edited robot.txt( User-agent: Twitterbot ,Disallow: ) to allow twitterbot access to my image folder. Please help me to solve this problem.