@fabioweb
Yes correctly, by default the single author is displayed by theme. The second author “Adriana Albini” was added with your plugin but i can’t see the picture
That is indeed correct that the second author is coming from our plugin, but the author box is being handled by your theme.
This means, the backend data is from our plugin, but the frontend display is from your theme.
In this case, you should also change the author box on the frontend to use from our plugin.
You could modify your theme to apply the author box from PublishPress Authors using this method: https://publishpress.com/knowledge-base/authors-byline-theme/ os using shortcode as per: https://publishpress.com/knowledge-base/shortcodes/
Let me know if you have any difficulties.
Thanks,