diff --git a/Test/Unit/Gateway/Http/Client/TransactionPaymentTest.php b/Test/Unit/Gateway/Http/Client/TransactionPaymentTest.php
index 2e5ff6526..c61cd35c2 100644
--- a/Test/Unit/Gateway/Http/Client/TransactionPaymentTest.php
+++ b/Test/Unit/Gateway/Http/Client/TransactionPaymentTest.php
@@ -6,7 +6,6 @@
 use Adyen\Payment\Model\PaymentResponse;
 use Adyen\Payment\Test\Unit\AbstractAdyenTestCase;
 use Adyen\Service\Checkout;
-use PHPUnit\Framework\TestCase;
 use Magento\Framework\TestFramework\Unit\Helper\ObjectManager;
 use Adyen\Payment\Helper\Data;
 use Adyen\Payment\Model\PaymentResponseFactory;
diff --git a/Test/Unit/Helper/PaymentDetailsTest.php b/Test/Unit/Helper/PaymentDetailsTest.php
new file mode 100644
index 000000000..303c37874
--- /dev/null
+++ b/Test/Unit/Helper/PaymentDetailsTest.php
@@ -0,0 +1,99 @@
+<?php
+/**
+ *
+ * Adyen Payment module (https://www.adyen.com/)
+ *
+ * Copyright (c) 2023 Adyen N.V. (https://www.adyen.com/)
+ * See LICENSE.txt for license details.
+ *
+ * Author: Adyen <magento@adyen.com>
+ */
+
+use Adyen\Payment\Helper\PaymentsDetails;
+use Adyen\Payment\Test\Unit\AbstractAdyenTestCase;
+use Magento\Sales\Api\Data\OrderInterface;
+use Magento\Sales\Model\Order\Payment;
+use Adyen\Payment\Helper\Data;
+use Adyen\Payment\Logger\AdyenLogger;
+use Adyen\Payment\Helper\PaymentResponseHandler;
+use Adyen\Payment\Helper\Idempotency;
+use Adyen\AdyenException;
+use Magento\Checkout\Model\Session;
+use Magento\Framework\Exception\ValidatorException;
+use Adyen\Service\Checkout;
+use Adyen\Client;
+
+class PaymentDetailsTest extends AbstractAdyenTestCase
+{
+    private $checkoutSessionMock;
+    private $adyenHelperMock;
+    private $adyenLoggerMock;
+    private $paymentResponseHandlerMock;
+    private $idempotencyHelperMock;
+    private $paymentDetails;
+
+    protected function setUp(): void
+    {
+        $this->checkoutSessionMock = $this->createMock(Session::class);
+        $this->adyenHelperMock = $this->createMock(Data::class);
+        $this->adyenLoggerMock = $this->createMock(AdyenLogger::class);
+        $this->paymentResponseHandlerMock = $this->createMock(PaymentResponseHandler::class);
+        $this->idempotencyHelperMock = $this->createMock(Idempotency::class);
+
+        $this->paymentDetails = new PaymentsDetails(
+            $this->checkoutSessionMock,
+            $this->adyenHelperMock,
+            $this->adyenLoggerMock,
+            $this->paymentResponseHandlerMock,
+            $this->idempotencyHelperMock
+            );
+    }
+
+    public function testRequestHeadersAreAddedToRequest()
+    {
+        $orderMock = $this->createMock(OrderInterface::class);
+        $paymentMock = $this->createMock(Payment::class);
+        $checkoutServiceMock = $this->createMock(Checkout::class);
+        $adyenClientMock = $this->createMock(Client::class);
+        $storeId = 1;
+        $payload = json_encode([
+            'details' => 'some_details',
+            'paymentData' => 'some_payment_data',
+            'threeDSAuthenticationOnly' => true
+        ]);
+        $requestOptions = [
+        'idempotencyKey' => 'some_idempotency_key',
+        'headers' => ['headerKey' => 'headerValue']
+        ];
+        $paymentDetailsResult = ['resultCode' => 'Authorised', 'action' => null, 'additionalData' => null];
+
+        $orderMock->method('getPayment')->willReturn($paymentMock);
+        $orderMock->method('getStoreId')->willReturn($storeId);
+        $paymentMock->method('getOrder')->willReturn($orderMock);
+
+        $this->adyenHelperMock->method('initializeAdyenClient')->willReturn($adyenClientMock);
+        $this->adyenHelperMock->method('createAdyenCheckoutService')->willReturn($checkoutServiceMock);
+        $this->adyenHelperMock->method('buildRequestHeaders')->willReturn($requestOptions['headers']);
+        $this->idempotencyHelperMock->method('generateIdempotencyKey')->willReturn($requestOptions['idempotencyKey']);
+
+        $checkoutServiceMock->expects($this->once())
+            ->method('paymentsDetails')
+            ->with(
+                $this->equalTo([
+                    'details' => 'some_details',
+                    'paymentData' => 'some_payment_data',
+                    'threeDSAuthenticationOnly' => true
+                ]),
+                $this->equalTo($requestOptions)
+            )
+            ->willReturn($paymentDetailsResult);
+
+        $this->paymentResponseHandlerMock->method('handlePaymentResponse')->willReturn(true);
+        $this->paymentResponseHandlerMock->method('formatPaymentResponse')->willReturn($paymentDetailsResult);
+
+        $result = $this->paymentDetails->initiatePaymentDetails($orderMock, $payload);
+
+        $this->assertJson($result);
+        $this->assertEquals(json_encode($paymentDetailsResult), $result);
+    }
+}