diff --git a/app/common/service/UsedCarDetailService.php b/app/common/service/UsedCarDetailService.php
index b77c5a3..e850758 100644
--- a/app/common/service/UsedCarDetailService.php
+++ b/app/common/service/UsedCarDetailService.php
@@ -1002,7 +1002,7 @@ class UsedCarDetailService
      */
     private function generateCode(): string
     {
-        return 'ST' . date('YmdHis') . rand(1000, 9999);
+        return 'ST' . date('mdHis') . rand(1000, 9999);
     }
 
     /**