Posting Errors

I get these three errors whenever I post to my blog. This is causing some strange behavior. First, it actually DOES post to facebook, twitter etc, as it should, but second, it doesn’t actually post to the main blog – you can get to each post by its direct URL, but not in the main blog feed. Also, it just posts these errors as though nothing happened – I have to reload the blog to see anything.

The blog is at https://stolendress.com/comedyonvinyl/wordpress/wordpress

ERRORS:

Warning: array_unique() expects parameter 1 to be array, null given in /home/stolen2/public_html/comedyonvinyl/wordpress/wordpress/wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/nxs_functions.php on line 51

Warning: Cannot modify header information – headers already sent by (output started at /home/stolen2/public_html/comedyonvinyl/wordpress/wordpress/wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/nxs_functions.php:51) in /home/stolen2/public_html/comedyonvinyl/wordpress/wordpress/wp-admin/post.php on line 235

Warning: Cannot modify header information – headers already sent by (output started at /home/stolen2/public_html/comedyonvinyl/wordpress/wordpress/wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/nxs_functions.php:51) in /home/stolen2/public_html/comedyonvinyl/wordpress/wordpress/wp-includes/pluggable.php on line 1121