ID affiliate not working

The plugin works fine in my site, but I have a problem because the tag ID_affiliate is not in the URL when I click in a product. (Amazon affiliate).

Could you show me an example of an Amazon affiliate feed URL working?

Here is an example of the URL I’m adding in the shortcode:
http://www.amazon.es/rss/new-releases/books/902675031/&tag=ID_Afiliado-21

https://wordpress.org/plugins/rss-via-shortcode-on-page-post/