Amazon not syndicating | CyberSEO Pro | Support Forum

This usually happens when you try to access this URL too often. Each search request causes a heavy load on a remote host because it performs a database query, so services like Amazon, Google etc. try to limit these requests and they temporarily ban your server's IP. In this situation, I would suggest that you wait a few hours and try again.

As for the URL itself. I've tried it on my test site and there's no problem with its syndication, so the problem seems to be a temporary ban of your IP on Amazon's side. You can also use proxies as an alternative solution to get around this restriction.