diff --git a/internal/web_server/handlers/maintenance_handler.go b/internal/web_server/handlers/maintenance_handler.go
index e429128..6e811c3 100644
--- a/internal/web_server/handlers/maintenance_handler.go
+++ b/internal/web_server/handlers/maintenance_handler.go
@@ -132,6 +132,45 @@ func (h *Handler) ResetAndReseedDatabase(c *fiber.Ctx) error {
 
 	var sqlBuilder strings.Builder
 	sqlBuilder.WriteString("BEGIN;\n")
+	// Ensure we never attempt to insert NULL set_id into question_set_items.
+	// Some deployments may already have the buggy function from migration 000024,
+	// so we patch it at runtime to make reseed safe.
+	sqlBuilder.WriteString(`
+CREATE OR REPLACE FUNCTION clone_default_initial_assessment_items(target_set_id BIGINT)
+RETURNS VOID AS $$
+DECLARE
+    template_set_id BIGINT;
+BEGIN
+    IF target_set_id IS NULL THEN
+        RETURN;
+    END IF;
+
+    SELECT id
+    INTO template_set_id
+    FROM question_sets
+    WHERE set_type = 'INITIAL_ASSESSMENT'
+      AND owner_type = 'STANDALONE'
+      AND status = 'PUBLISHED'
+    ORDER BY created_at DESC
+    LIMIT 1;
+
+    IF template_set_id IS NULL THEN
+        RETURN;
+    END IF;
+
+    INSERT INTO question_set_items (set_id, question_id, display_order)
+    SELECT target_set_id, qsi.question_id, qsi.display_order
+    FROM question_set_items qsi
+    WHERE qsi.set_id = template_set_id
+      AND NOT EXISTS (
+          SELECT 1
+          FROM question_set_items existing
+          WHERE existing.set_id = target_set_id
+            AND existing.question_id = qsi.question_id
+      );
+END;
+$$ LANGUAGE plpgsql;
+`)
 	sqlBuilder.WriteString(`
 DO $$
 DECLARE