Originally Posted by Craig Tuller
Try replacing your code with this:
<a href="http://www.rhpa.org/index.php/products/profile/07493509/subscribe.rhpa" ><img src="http://www.vibrantlife.com/wp-content/uploads/2010/03/sub_adtop.gif" alt="Subscribe to Vibrant Life" /></a>
I found the real problem there is difference between the ad block at the header and the ad block that displays between post and comments.
The ad block in the header is change in the Widgets section and the ad block that display between comments in change in the Lifestyle Theme Options section under appearance in the admin section.
Have a good day!