diff --git a/docker-compose.yml b/docker-compose.yml
index 39a969b..421c262 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -12,3 +12,4 @@ services:
 
 volumes:
   packliste_uploads:
+    external: true
diff --git a/src/api_packing_list_handler.php b/src/api_packing_list_handler.php
index 8758a9a..22017e9 100644
--- a/src/api_packing_list_handler.php
+++ b/src/api_packing_list_handler.php
@@ -75,7 +75,7 @@ try {
             foreach ($items_from_frontend as $index => $item_data) {
                 $pli_id_frontend = $item_data['pli_id'];
                 $article_id = intval($item_data['article_id']);
-                $carrier_id = ($item_data['carrier_id'] === 'null') ? NULL : intval($item_data['carrier_id']);
+                $carrier_id = ($item_data['carrier_id'] === 'null' || $item_data['carrier_id'] === null) ? NULL : intval($item_data['carrier_id']);
                 
                 // New fields
                 $backpack_id = !empty($item_data['backpack_id']) ? intval($item_data['backpack_id']) : NULL;
@@ -129,8 +129,11 @@ try {
                         foreach ($child_items as $child) {
                             $temp_index++;
                             // Child items are normal items
-                            $stmt_insert->bind_param("iiiiiiiis", $packing_list_id, $child['id'], 1, $carrier_id, $temp_index, $new_db_id, $null_val, $null_val, $null_val);
-                            $null_val = NULL; 
+                            $null_val1 = NULL;
+                            $null_val2 = NULL;
+                            $null_val3 = NULL;
+                            $qty_one = 1;
+                            $stmt_insert->bind_param("iiiiiiiis", $packing_list_id, $child['id'], $qty_one, $carrier_id, $temp_index, $new_db_id, $null_val1, $null_val2, $null_val3);
                             if(!$stmt_insert->execute()) throw new Exception("Fehler beim Einfügen von Kind-Artikel " . $child['id']);
                         }
                     }
@@ -250,6 +253,7 @@ try {
     if ($conn) {
         try { $conn->rollback(); } catch (Throwable $t) {}
     }
+    file_put_contents(__DIR__ . '/api_error.log', date('Y-m-d H:i:s') . ' - ERROR: ' . $e->getMessage() . "\n" . $e->getTraceAsString() . "\n\n", FILE_APPEND);
     http_response_code(500);
     echo json_encode(['error' => $e->getMessage()]);
 } finally {