Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "callback" not found or invalid function name in /home/humbercaststonec/public_html/wp-includes/class-wp-hook.php:324 Stack trace: #0 /home/humbercaststonec/public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters('', Array) #1 /home/humbercaststonec/public_html/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #2 /home/humbercaststonec/public_html/wp-content/plugins/woocommerce/includes/class-woocommerce.php(865): do_action('woocommerce_ini...') #3 /home/humbercaststonec/public_html/wp-includes/class-wp-hook.php(324): WooCommerce->init('') #4 /home/humbercaststonec/public_html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array) #5 /home/humbercaststonec/public_html/wp-includes/plugin.php(517): WP_Hook->do_action(Array) #6 /home/humbercaststonec/public_html/wp-settings.php(727): do_action('init') #7 /home/humbercaststonec/public_html/wp-config.php(109): require_once('/home/humbercas...') #8 /home/humbercaststonec/public_html/wp-load.php(50): require_once('/home/humbercas...') #9 /home/humbercaststonec/public_html/wp-blog-header.php(13): require_once('/home/humbercas...') #10 /home/humbercaststonec/public_html/index.php(17): require('/home/humbercas...') #11 {main} thrown in /home/humbercaststonec/public_html/wp-includes/class-wp-hook.php on line 324