Fatal error: Uncaught Error: Call to undefined function register_block_type() in /home/etrix1bg/www.hotel-balkan.com/wp-content/plugins/ninja-forms/blocks/bootstrap.php:21 Stack trace: #0 /home/etrix1bg/www.hotel-balkan.com/wp-includes/class-wp-hook.php(286): Ninja_Forms::{closure}('') #1 /home/etrix1bg/www.hotel-balkan.com/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(true, Array) #2 /home/etrix1bg/www.hotel-balkan.com/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #3 /home/etrix1bg/www.hotel-balkan.com/wp-settings.php(450): do_action('init') #4 /home/etrix1bg/www.hotel-balkan.com/wp-config.php(93): require_once('/home/etrix1bg/...') #5 /home/etrix1bg/www.hotel-balkan.com/wp-load.php(37): require_once('/home/etrix1bg/...') #6 /home/etrix1bg/www.hotel-balkan.com/wp-blog-header.php(13): require_once('/home/etrix1bg/...') #7 /home/etrix1bg/www.hotel-balkan.com/index.php(17): require('/home/etrix1bg/...') #8 {main} thrown in /home/etrix1bg/www.hotel-balkan.com/wp-content/plugins/ninja-forms/blocks/bootstrap.php on line 21