diff --git a/app/PaymentDrivers/PayPalExpressPaymentDriver.php b/app/PaymentDrivers/PayPalExpressPaymentDriver.php
index 43b2a6a1ad4a..75a569c84c81 100644
--- a/app/PaymentDrivers/PayPalExpressPaymentDriver.php
+++ b/app/PaymentDrivers/PayPalExpressPaymentDriver.php
@@ -93,7 +93,7 @@ class PayPalExpressPaymentDriver extends BaseDriver
             return $response->redirect();
         }
 
-        $this->sendFailureMail($response->getMessage());
+        $this->sendFailureMail($response->getMessage() ?: '');
 
         $message = [
             'server_response' => $response->getMessage(),
@@ -151,7 +151,7 @@ class PayPalExpressPaymentDriver extends BaseDriver
 
             $data = $response->getData();
             
-            $this->sendFailureMail($response->getMessage());
+            $this->sendFailureMail($response->getMessage() ?: '');
 
             $message = [
                 'server_response' => $data['L_LONGMESSAGE0'],