diff --git a/WePayV3/Transfers.php b/WePayV3/Transfers.php
index 7e3939b..d32289b 100644
--- a/WePayV3/Transfers.php
+++ b/WePayV3/Transfers.php
@@ -42,12 +42,12 @@ class Transfers extends BasicWePay
             foreach ($body['transfer_detail_list'] as &$item) if (isset($item['user_name'])) {
                 $item['user_name'] = $this->rsaEncode($item['user_name']);
             }
-        }
-        if (empty($body['total_num'])) {
-            $body['total_num'] = count($body['transfer_detail_list']);
-        }
-        if (empty($body['total_amount'])) {
-            $body['total_amount'] = array_sum(array_column($body['transfer_detail_list'], 'transfer_amount'));
+            if (empty($body['total_num'])) {
+                $body['total_num'] = count($body['transfer_detail_list']);
+            }
+            if (empty($body['total_amount'])) {
+                $body['total_amount'] = array_sum(array_column($body['transfer_detail_list'], 'transfer_amount'));
+            }
         }
         return $this->doRequest('POST', '/v3/transfer/batches', json_encode($body, JSON_UNESCAPED_UNICODE), true);
     }