From 347ae2db5e192281790d80578bc0e9f746d27caa Mon Sep 17 00:00:00 2001
From: Fabian Boettcher <fabian.boettcher@payone.de>
Date: Wed, 5 Feb 2020 16:14:32 +0100
Subject: [PATCH] Fix logic bug in refund sequence number check

---
 src/Payone/Request/Refund/RefundRequest.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Payone/Request/Refund/RefundRequest.php b/src/Payone/Request/Refund/RefundRequest.php
index 86a98bbc4..2ebb8a3cb 100644
--- a/src/Payone/Request/Refund/RefundRequest.php
+++ b/src/Payone/Request/Refund/RefundRequest.php
@@ -32,7 +32,7 @@ public function getRequestParameters(
             throw new InvalidOrderException($order->getId());
         }
 
-        if (empty($customFields[CustomFieldInstaller::SEQUENCE_NUMBER])) {
+        if (!isset($customFields[CustomFieldInstaller::SEQUENCE_NUMBER])) {
             throw new InvalidOrderException($order->getId());
         }