diff --git a/app/Service/PaymentService.php b/app/Service/PaymentService.php
index 977ecaf..eacafe9 100644
--- a/app/Service/PaymentService.php
+++ b/app/Service/PaymentService.php
@@ -88,7 +88,7 @@ class PaymentService extends AbstractService
 
     public function notify($params) {
         Log::info('notify:', $params, 'omipay');
-        if (Signer::verify($params)) {
+        if (!Signer::verify($params)) {
             return 'SIGN FAIL';
         }
         if ($params['return_code'] != 'SUCCESS') {