Feed Items or Posts Not Importing - Clear Cache
Caching Plugin Issues
It is known to the WP RSS Aggregator developers that certain caching plugins cause some issues when used with WP RSS Aggregator, one of which could be the duplication of posts. These issues might vary depending on the caching plugin in use and the settings implemented.
Why is dynamic content, such as an RSS feed, a problem for caching plugins?
Caching plugins, and sometimes host server caching, do not have a way to detect and flush the cache for updated dynamic content. Thus, content on the site such as an RSS feed don't update properly when your site is being cached.
It is necessary to clear the cache files to avoid duplicate feed items or for feed items to update on the front end of your site.
If your theme or plugin that you installed is not clearing the cache automatically, we recommend contacting the plugin developer and asking if the plugin is compatible with dynamic content.