Fatal error: Uncaught Error: Call to undefined function add_action() in /home/cezarypiatek1990/public_html/testwordpressa/wp-content/themes/twentytwentyone/inc/back-compat.php:24 Stack trace: #0 {main} thrown in /home/cezarypiatek1990/public_html/testwordpressa/wp-content/themes/twentytwentyone/inc/back-compat.php on line 24