Most probably the code you put is for the wordpress.com blogs.
If your blog's installation is on a self-hosted wordpress.org platform, blogger or typepad,
then remove the code you have already added to you blog and grab the first code of the code dialog, as shown below:
This will display the linkup inside the blog post.
If your blog hosted on wordpress.com, then no widget is allowed to be displayed inside your posts.
For this kind of installations, you can only use the second code of the code dialog which presents a button for your users to see the linkup on an external page.