Header doesn't appear on Vendor page

Hello,

I’m building an e-commerce website and I’m trying to add different header images for each vendor. I’ve added a header for the vendor Uppercut but it doesn’t appear on the page. Can you tell me what I have to do to make it appear?

http://shoplocal.greaterinverness.com/vendor/uppercut/

http://wordpress.org/plugins/wp-display-header/