Fatal error: Uncaught TypeError: Argument 1 passed to TUTOR\Course_List::is_public() must be of the type int, null given, called in /www/wwwroot/hive.courses/wp-content/plugins/tutor/templates/single/lesson/lesson_sidebar.php on line 37 and defined in /www/wwwroot/hive.courses/wp-content/plugins/tutor/classes/Course_List.php:526 Stack trace: #0 /www/wwwroot/hive.courses/wp-content/plugins/tutor/templates/single/lesson/lesson_sidebar.php(37): TUTOR\Course_List::is_public() #1 /www/wwwroot/hive.courses/wp-content/plugins/tutor/includes/tutor-template-functions.php(130): include('/www/wwwroot/hi...') #2 /www/wwwroot/hive.courses/wp-content/plugins/tutor/templates/single-content-loader.php(41): tutor_load_template() #3 /www/wwwroot/hive.courses/wp-content/plugins/tutor/templates/single-content-loader.php(68): tutor_course_single_sidebar() #4 /www/wwwroot/hive.courses/wp-content/plugins/tutor/includes/tutor-template-functions.php(1571): include('/www/wwwroot/hi...') #5 /www/wwwroot/hive.courses/wp-content/plugins/tutor/templat in /www/wwwroot/hive.courses/wp-content/plugins/tutor/classes/Course_List.php on line 526