Why do I have this warning?

Warning: strpos(): Empty needle in /home/MyDataBase/public_html/wp-content/plugins/feedzy-rss-feeds/feedzy-rss-feeds-functions.php on line 191

I have the widget code on a Page (that right now is set to: Private)and set to this:

[feedzy-rss feeds=”1st-feed-link,2nd-feed-link,3rd-feed-link,” max=”10″ target=”_blank” title=”25″ meta=”yes” summary=”yes” summarylength=”300″ thumb=”yes” default=”http://mysite.com/wp-content/uploads/2015/03/pic.png” size=”150″ keywords_title=”1stkeyword,2ndkeyword,3rdkeyword,etc,”]

https://wordpress.org/plugins/feedzy-rss-feeds/