diff --git a/src/DotpayApi/Client.php b/src/DotpayApi/Client.php
index b6466d7..c57751f 100644
--- a/src/DotpayApi/Client.php
+++ b/src/DotpayApi/Client.php
@@ -44,6 +44,7 @@ public function __construct($username, $password, $base_url)
     /**
      * @param IRequest $request
      * @return mixed
+     * @throws \GuzzleHttp\Exception\GuzzleException
      */
     public function makeRequest(IRequest $request)
     {
diff --git a/src/DotpayApi/DotpayApi.php b/src/DotpayApi/DotpayApi.php
index a0519d1..68deebd 100644
--- a/src/DotpayApi/DotpayApi.php
+++ b/src/DotpayApi/DotpayApi.php
@@ -43,6 +43,7 @@ public function __construct($config)
     /**
      * @param $payment
      * @return mixed|string
+     * @throws \GuzzleHttp\Exception\GuzzleException
      */
     public function createPayment($payment)
     {
@@ -51,10 +52,13 @@ public function createPayment($payment)
 
     /**
      * @param $payment
+     * @param $operation_number
      * @return mixed
+     * @throws \Evilnet\Dotpay\Exceptions\RequestIntegrityException
+     * @throws \GuzzleHttp\Exception\GuzzleException
      */
-    public function refundPayment($payment){
-        return $this->client->makeRequest(new CreateRefund($this->config['shop_id'], $payment));
+    public function refundPayment($operation_number, $payment){
+        return $this->client->makeRequest(new CreateRefund($operation_number, $payment));
     }
 
     /**
@@ -82,5 +86,4 @@ public function verifyCallback($data)
     {
         return $this->validator->verify($data);
     }
-
 }
diff --git a/src/DotpayApi/Response.php b/src/DotpayApi/Response.php
index 0dcb7b6..1a599e8 100644
--- a/src/DotpayApi/Response.php
+++ b/src/DotpayApi/Response.php
@@ -77,5 +77,4 @@ public function getOperationStatus()
     {
         return $this->data['operation_status'];
     }
-
 }
diff --git a/src/DotpayApi/UrlCreator.php b/src/DotpayApi/UrlCreator.php
index 0524be4..67e3c44 100644
--- a/src/DotpayApi/UrlCreator.php
+++ b/src/DotpayApi/UrlCreator.php
@@ -39,5 +39,4 @@ public function getPaymentUrlWithCHK($payment)
     {
         return $payment->payment_url.'&chk='.hash('sha256', ($this->pin.$payment->token));
     }
-
 }
diff --git a/src/DotpayApi/Validator.php b/src/DotpayApi/Validator.php
index 0b7e13e..d3422a7 100644
--- a/src/DotpayApi/Validator.php
+++ b/src/DotpayApi/Validator.php
@@ -69,5 +69,4 @@ public function verify($data)
 
         return $data['signature'] === $hash;
     }
-
 }
diff --git a/src/DotpayManager.php b/src/DotpayManager.php
index 9614fae..7b7cdc2 100644
--- a/src/DotpayManager.php
+++ b/src/DotpayManager.php
@@ -35,6 +35,7 @@ public function __construct(DotpayApi $dotpayApi)
     /**
      * @param $data
      * @return mixed|string
+     * @throws \GuzzleHttp\Exception\GuzzleException
      */
     public function createPayment($data)
     {
@@ -42,11 +43,14 @@ public function createPayment($data)
     }
 
     /**
+     * @param $operation_number
      * @param $data
      * @return mixed
+     * @throws Exceptions\RequestIntegrityException
+     * @throws \GuzzleHttp\Exception\GuzzleException
      */
-    public function refundPayment($data){
-        return $this->dotpayApi->refundPayment($data);
+    public function refundPayment($operation_number, $data){
+        return $this->dotpayApi->refundPayment($operation_number, $data);
     }