diff --git a/backend/app/Controllers/ExamController.php b/backend/app/Controllers/ExamController.php
index cd0d0dc..01ef77c 100644
--- a/backend/app/Controllers/ExamController.php
+++ b/backend/app/Controllers/ExamController.php
@@ -436,11 +436,11 @@ class ExamController
         if (!$examId) {
             $examId = (int)Database::insert(
                 "INSERT INTO exams (uuid, course_id, lesson_id, creator_type, scope, title, passing_percentage, total_points, duration_minutes, is_mandatory, is_published)
-                 VALUES (UUID(), 1, 0, 'ai_adaptive', 'unit_exam', 'اختبار الفهم الشامل: الوحدة الأولى — أنظمة المعادلات', 70.00, 100, 45, 1, 1)"
+                 VALUES (UUID(), 1, NULL, 'ai_adaptive', 'unit_exam', 'اختبار الفهم الشامل: الوحدة الأولى — أنظمة المعادلات', 70.00, 100, 45, 1, 1)"
             );
         } else {
             Database::query(
-                "UPDATE exams SET title = 'اختبار الفهم الشامل: الوحدة الأولى — أنظمة المعادلات', duration_minutes = 45, total_points = 100, passing_percentage = 70.00, scope = 'unit_exam', is_published = 1 WHERE id = ?",
+                "UPDATE exams SET title = 'اختبار الفهم الشامل: الوحدة الأولى — أنظمة المعادلات', duration_minutes = 45, total_points = 100, passing_percentage = 70.00, scope = 'unit_exam', lesson_id = NULL, is_published = 1 WHERE id = ?",
                 [$examId]
             );
         }
diff --git a/backend/app/Services/AiQuestionBankGeneratorService.php b/backend/app/Services/AiQuestionBankGeneratorService.php
index 70a1afa..434ded8 100644
--- a/backend/app/Services/AiQuestionBankGeneratorService.php
+++ b/backend/app/Services/AiQuestionBankGeneratorService.php
@@ -61,6 +61,15 @@ class AiQuestionBankGeneratorService
             $aiQuestions = self::synthesizeQuestionsFromMarkdown($mdFiles, $targetCount);
         }
 
+        // Ensure valid course_id exists in database
+        $courseCheck = Database::selectOne("SELECT id FROM courses WHERE id = ? LIMIT 1", [$courseId]);
+        if (!$courseCheck) {
+            $firstCourse = Database::selectOne("SELECT id FROM courses LIMIT 1");
+            if ($firstCourse) {
+                $courseId = (int)$firstCourse['id'];
+            }
+        }
+
         // Ensure Unit Exam exists in database
         $exam = Database::selectOne(
             "SELECT id FROM exams WHERE course_id = ? AND (scope = 'unit_exam' OR scope = 'unit_comprehensive') AND (title LIKE ? OR title LIKE '%الوحدة الأولى%') LIMIT 1",
@@ -71,12 +80,12 @@ class AiQuestionBankGeneratorService
         if (!$examId) {
             $examId = (int)Database::insert(
                 "INSERT INTO exams (uuid, course_id, lesson_id, creator_type, scope, title, duration_minutes, passing_percentage, total_points, is_mandatory, is_published)
-                 VALUES (UUID(), ?, 0, 'ai_adaptive', 'unit_exam', ?, 45, 70.00, 100, 1, 1)",
+                 VALUES (UUID(), ?, NULL, 'ai_adaptive', 'unit_exam', ?, 45, 70.00, 100, 1, 1)",
                 [$courseId, "اختبار الفهم الشامل: {$unitTitle}"]
             );
         } else {
             Database::query(
-                "UPDATE exams SET title = ?, duration_minutes = 45, scope = 'unit_exam', is_published = 1 WHERE id = ?",
+                "UPDATE exams SET title = ?, duration_minutes = 45, scope = 'unit_exam', lesson_id = NULL, is_published = 1 WHERE id = ?",
                 ["اختبار الفهم الشامل: {$unitTitle}", $examId]
             );
         }