edit

lib/Wechat.php

@@ -110,7 +110,7 @@ class Wechat extends Core
 	{
 		if (isset($order['prepay_id'])) {
 			$order['partnerid'] = $this->config->GetMerchantId();
-			$order['package'] = 'Sign=WXPay';
+			$order['package_string'] = 'Sign=WXPay';
 
 			$string = 'appid='.$this->config->GetAppId().'&partnerid='.$order['partnerid'].'&prepayid='.$order['prepay_id'].'&package='.$order['package'].'&noncestr='.$order['nonce_str'].'&timestamp='.$order['time'];
 			if($order['sign_type'] == "MD5"){