Everytime I log into my WP site I get the error below. This started a few days ago after I changed my theme and I can't seem to get it fixed. It only shows this, I can't even get back to anything to change it back or try to fix it. Here is the error:
Fatal error: Cannot redeclare setting_pass_fn() (previously declared in /home/mystuff/public_html/wp-content/plugins/open-menu/openmenu.php:566) in /home/mystuff/public_html/wp-content/themes/zombie-apocalypse/zombie-admin-functions.php on line 559.
I changed the original name here to "mystuff" but everything else is exactly as shown.
I would really appreciate any help here, but please be descriptive with your answer. In other words, I am really new to WordPress and HTML and do not know where to go to fix this or how to get there! So a specific and detailed walkthrough with exactly what I need to do would be most helpful. Thank you to everyone in advance for any and all help you can provide for me.