Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, first array member is not a valid class name or object in /home/minervanpollo/public/html/wp-includes/class-wp-hook.php:307
Stack trace:
#0 /home/minervanpollo/public/html/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters(NULL, Array)
#1 /home/minervanpollo/public/html/wp-includes/plugin.php(474): WP_Hook->do_action(Array)
#2 /home/minervanpollo/public/html/wp-includes/general-template.php(3042): do_action('wp_head')
#3 /home/minervanpollo/public/html/wp-content/themes/toolbox/header.php(56): wp_head()
#4 /home/minervanpollo/public/html/wp-includes/template.php(770): require_once('/home/minervanp...')
#5 /home/minervanpollo/public/html/wp-includes/template.php(716): load_template('/home/minervanp...', true, Array)
#6 /home/minervanpollo/public/html/wp-includes/general-template.php(48): locate_template(Array, true, true, Array)
#7 /home/minervanpollo/public/html/wp-content/themes/toolbox/single.php(9): get_header()
#8 /home/minervanpollo/public/html/wp-includes/template-loader.php(106): include('/home/minervanp...')
#9 /home/minervanpollo/public/html/wp-blog-header.php(19): require_once('/home/minervanp...')
#10 /home/minervanpollo/public/html/index.php(17): require('/home/minervanp...')
#11 {main}
thrown in /home/minervanpollo/public/html/wp-includes/class-wp-hook.php on line 307