Twitter cards only works in one post


I have a problem whith twitter cards. I follow every step to activate the cards and I received the confirmation mail. My web is whitelisted and everything is on green. But when I want to share a post the card is not displayed… It only work whith a single post of my blog.
My site is wordpress made and I have the JM twitter cards plugin to configure everything.
What´s wrong? Why only works whith a single post?

Thank you in advance.
My site is


I have exactly the same problem. I have received the domain approval email and blog is on

It works fine with this post but not with any others e.g.

I’m not sure if this is related but the URL that does work was, I am pretty sure, the URL I used in the card validator originally to get the “request domain approval” option.

Any help much appreciated! thanks.