I am having the same issue, and all settings are correct and accurate.
I am creating posts automatically to the News category using RSS Post Importer:
https://wordpress.org/plugins/rss-post-importer/
And I have WP-to-buffer set for all new posts on publish.
My guess is that the plugin does not register these are new published posts. How can I correct this?
WP and both plugins are at the latest versions.
