diff --git a/Gateway/Http/Client/TransactionCapture.php b/Gateway/Http/Client/TransactionCapture.php
index 0ed6dbb10..05a71cbd7 100644
--- a/Gateway/Http/Client/TransactionCapture.php
+++ b/Gateway/Http/Client/TransactionCapture.php
@@ -72,8 +72,6 @@ public function placeRequest(TransferInterface $transferObject): array
     {
         $request = $transferObject->getBody();
         $headers = $transferObject->getHeaders();
-        $idempotencyKeyExtraData = $headers['idempotencyExtraData'];
-        unset($headers['idempotencyExtraData']);
         $clientConfig = $transferObject->getClientConfig();
 
         $client = $this->adyenHelper->initializeAdyenClientWithClientConfig($clientConfig);
@@ -86,6 +84,9 @@ public function placeRequest(TransferInterface $transferObject): array
             return $this->placeMultipleCaptureRequests($service, $request, $requestOptions);
         }
 
+        $idempotencyKeyExtraData = $request['idempotencyExtraData'];
+        unset($request['idempotencyExtraData']);
+
         $idempotencyKey = $this->idempotencyHelper->generateIdempotencyKey(
             $request,
             $idempotencyKeyExtraData ?? null
diff --git a/Gateway/Request/CaptureDataBuilder.php b/Gateway/Request/CaptureDataBuilder.php
index 99b3d2354..ff8ce9557 100644
--- a/Gateway/Request/CaptureDataBuilder.php
+++ b/Gateway/Request/CaptureDataBuilder.php
@@ -109,7 +109,10 @@ public function build(array $buildSubject): array
         $requestBody = [
             "amount" => $modificationAmount,
             "reference" => $payment->getOrder()->getIncrementId(),
-            "paymentPspReference" => $pspReference
+            "paymentPspReference" => $pspReference,
+            "idempotencyExtraData" => [
+                'totalInvoiced' => $payment->getOrder()->getTotalInvoiced() ?? 0
+            ]
         ];
 
         //Check additionaldata
@@ -119,11 +122,6 @@ public function build(array $buildSubject): array
         }
         $request['body'] = $requestBody;
         $request['clientConfig'] = ["storeId" => $payment->getOrder()->getStoreId()];
-        $request['headers'] = [
-            'idempotencyExtraData' => [
-                'totalInvoiced' => $payment->getOrder()->getTotalInvoiced() ?? 0
-            ]
-        ];
 
         return $request;
     }
diff --git a/Test/Unit/Gateway/Http/Client/TransactionCaptureTest.php b/Test/Unit/Gateway/Http/Client/TransactionCaptureTest.php
index 19348bed5..801c94f77 100644
--- a/Test/Unit/Gateway/Http/Client/TransactionCaptureTest.php
+++ b/Test/Unit/Gateway/Http/Client/TransactionCaptureTest.php
@@ -43,11 +43,12 @@ protected function setUp(): void
             'amount' => ['value' => 100, 'currency' => 'USD'],
             'paymentPspReference' => 'testPspReference',
             'applicationInfo' => $applicationInfo,
+            'idempotencyExtraData' => ['someData']
         ];
 
         $this->transferObject = $this->createConfiguredMock(TransferInterface::class, [
             'getBody' => $this->request,
-            'getHeaders' => ['idempotencyExtraData' => ['someData']],
+            'getHeaders' => [],
             'getClientConfig' => []
         ]);
     }
@@ -63,10 +64,13 @@ private function configureAdyenMocks(array $response = null, \Exception $excepti
         $this->adyenHelper->method('buildRequestHeaders')->willReturn([]);
         $this->adyenHelper->expects($this->once())->method('logRequest');
 
+        $trimmedRequest = $this->request;
+        unset($trimmedRequest['idempotencyExtraData']);
+
         $this->idempotencyHelper->expects($this->once())
             ->method('generateIdempotencyKey')
             ->with(
-                $this->request,
+                $trimmedRequest,
                 $this->equalTo(['someData'])
             )
             ->willReturn($expectedIdempotencyKey);