View More button doesn't work

Hello:

My website is already done, except for the view more button used on the Post Grid plugin.

When I load the page it appears with this code, instead of a button:

[vc_btn link="post_link" title="Read more" style="flat" shape="rounded" color="juicy-pink" size="md" align="left"]

The link is http://www.v10solutions.com/ciencia/

What could be happening?

Thank you in advance.

https://wordpress.org/plugins/post-grid/