Warning messages in Origami theme

Every time I edit a page or save my changes, this comes up in a new window…

Warning: call_user_func_array() expects parameter 1 to be a valid callback, function ‘ola_mc_update_campaign_content’ not found or invalid function name in /home/sruslacker/public_html/wp-includes/plugin.php on line 496

Warning: Cannot modify header information – headers already sent by (output started at /home/sruslacker/public_html/wp-includes/plugin.php:496) in /home/sruslacker/public_html/wp-admin/post.php on line 233

Warning: Cannot modify header information – headers already sent by (output started at /home/sruslacker/public_html/wp-includes/plugin.php:496) in /home/sruslacker/public_html/wp-includes/pluggable.php on line 1178

If I go back to the previous page, my changes are lost and when I make the changes again, it usually works. It is getting very frustrating and I dont know what the warnings are for or how to fix the problem.

Help!