Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, class "BiqSF\ACF" not found in /var/www/biq-shop.de/wp-includes/class-wp-hook.php:324 Stack trace: #0 /var/www/biq-shop.de/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters() #1 /var/www/biq-shop.de/wp-includes/plugin.php(517): WP_Hook->do_action() #2 /var/www/biq-shop.de/wp-content/plugins/advanced-custom-fields-pro/acf.php(424): do_action() #3 /var/www/biq-shop.de/wp-includes/class-wp-hook.php(324): ACF->init() #4 /var/www/biq-shop.de/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters() #5 /var/www/biq-shop.de/wp-includes/plugin.php(517): WP_Hook->do_action() #6 /var/www/biq-shop.de/wp-settings.php(704): do_action() #7 /var/www/biq-shop.de/wp-config.php(100): require_once('...') #8 /var/www/biq-shop.de/wp-load.php(50): require_once('...') #9 /var/www/biq-shop.de/wp-blog-header.php(13): require_once('...') #10 /var/www/biq-shop.de/index.php(17): require('...') #11 {main} thrown in /var/www/biq-shop.de/wp-includes/class-wp-hook.php on line 324