diff --git a/webht/third_party/paypal/controllers/index.php b/webht/third_party/paypal/controllers/index.php
index 7a1b2ed5..3c0a9303 100644
--- a/webht/third_party/paypal/controllers/index.php
+++ b/webht/third_party/paypal/controllers/index.php
@@ -1386,7 +1386,7 @@ class Index extends CI_Controller {
         // 记录这次导出的最后一条
         if (isset($all_list['last_flag']) && ! empty($all_list['last_flag'])) {
             $balance_diff = bcsub($all_list['now_amount'], $amount);
-            $last_record_export = bcsub($all_list['last_flag']->pn_mc_gross, $balance_diff);
+            $last_record_export = $balance_diff>0 ? bcsub($all_list['last_flag']->pn_mc_gross, $balance_diff) : $all_list['last_flag']->pn_mc_gross;
             $insert_db = array(
                 "TEL_transactionType" => 15002
                 ,"TEL_transactionNoticeId" => $all_list['last_flag']->pn_sn