Call to undefined method WP_Error::enable_order_by_date()

I have the same problem ??

[rssonpage rss = “https://www.conjur.com.br/rss.xml” feeds = “2” excerpt = “false” target = “_ blank”]

[rssonpage rss = “https://stf.jus.br/portal/RSS/noticiaRss.asp?codigo=1” feeds = “2” excerpt = “false” target = “_ blank”]

Fatal error: Call to undefined method WP_Error :: enable_order_by_date () in /home/cruzcost/public_html/wp-content/plugins/rss-via-shortcode-on-page-post/rss-via-shortcode.php on line 23

Any ideas??

Still no solution?

https://gist.github.com/tlongren/c6ea073ebf616edd5db89d9c663c2c62