ERROR: Blocked by robots.txt (og:image)

I am using your plugin and I like the way that it is set up. But I’m having a few issues.

I set it up using the Summary Large Image card, everything works fine. Title pulls in, description, twitter username but no image. I read in a previous post to try and submit it with a Photo Card, which I did. This is the error I get:

ERROR: Blocked by robots.txt (og:image)

Here’s what I have in my robots.txt:

User-agent: Twitterbot
Disallow:

User-agent: *
Disallow: /wp-admin/
Sitemap: http://www.trillmatic.com/sitemap.xml

For added measure, I’m currently using the Falcon Engine caching from Wordfence and MaxCDN using the CDN Linker plugin. All plugins and wordpress is update to the latest.

All I want is the image to be pulled from the featured image from the post to show up on the twitter card. Please advise of the what I’m doing wrong.

https://wordpress.org/plugins/jm-twitter-cards/