Cannot Show Ad In Paragraph

I have asked that a 250×250 google adsense ad be shown after the 2nd paragraph but it is not showing.

The bigger ad I asked to show at the ‘End of Post’ is working fine however.

Here’s a post that should really have an ad showing but doesn’t.

http://www.gameralert.co.uk/filthy-lucre-pc-release-date/

The ad code is fine because I am using the same one in the Sidebar.