diff --git a/wx/V3/WxV3PaymentTait.php b/wx/V3/WxV3PaymentTait.php
index 1c08ac0..19a83f4 100644
--- a/wx/V3/WxV3PaymentTait.php
+++ b/wx/V3/WxV3PaymentTait.php
@@ -75,8 +75,8 @@ trait WxV3PaymentTait
     {
         $config   = $this->getPayConfig();
         $parseUrl = '/v3/pay/transactions/out-trade-no/' . $orderNo;
-        $sign     = $this->signature('POST', $parseUrl, $json = json_encode(['mchid' => $config->pay->wx->mchId]));
-        $client   = $this->createClient($sign, $json);
+        $sign     = $this->signature('POST', $parseUrl . '?mchid=' . $config->pay->wx->mchId, null);
+        $client   = $this->createClient($sign, null);
         $client->get($parseUrl, ['mchid' => $config->pay->wx->mchId]);
         $client->close();