diff --git a/src/Message/CompletePurchaseRequest.php b/src/Message/CompletePurchaseRequest.php
index 8850e93..e058770 100644
--- a/src/Message/CompletePurchaseRequest.php
+++ b/src/Message/CompletePurchaseRequest.php
@@ -4,222 +4,28 @@
 
 use Ecpay\Sdk\Response\VerifiedArrayResponse;
 use Exception;
-use Omnipay\Common\Exception\InvalidRequestException;
 use Omnipay\Common\Exception\InvalidResponseException;
 use Omnipay\Common\Message\AbstractRequest;
-use Omnipay\ECPay\Traits\HasCustomFields;
 use Omnipay\ECPay\Traits\HasDefaults;
 use Omnipay\ECPay\Traits\HasECPay;
-use Omnipay\ECPay\Traits\HasMerchantTradeNo;
-use Omnipay\ECPay\Traits\HasStoreID;
 
 class CompletePurchaseRequest extends AbstractRequest
 {
     use HasECPay;
     use HasDefaults;
-    use HasMerchantTradeNo;
-    use HasStoreID;
-    use HasCustomFields;
-
-    /**
-     * @return string
-     */
-    public function getPaymentDate()
-    {
-        return $this->getParameter('PaymentDate');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setPaymentDate($value)
-    {
-        return $this->setParameter('PaymentDate', $value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getPaymentType()
-    {
-        return $this->getParameter('PaymentType');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setPaymentType($value)
-    {
-        return $this->setParameter('PaymentType', $value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getPaymentTypeChargeFee()
-    {
-        return $this->getParameter('PaymentTypeChargeFee');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setPaymentTypeChargeFee($value)
-    {
-        return $this->setParameter('PaymentTypeChargeFee', $value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getRtnCode()
-    {
-        return $this->getParameter('RtnCode');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setRtnCode($value)
-    {
-        return $this->setParameter('RtnCode', $value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getRtnMsg()
-    {
-        return $this->getParameter('RtnMsg');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setRtnMsg($value)
-    {
-        return $this->setParameter('RtnMsg', $value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getSimulatePaid()
-    {
-        return $this->getParameter('SimulatePaid');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setSimulatePaid($value)
-    {
-        return $this->setParameter('SimulatePaid', $value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getTradeAmt()
-    {
-        return $this->getParameter('TradeAmt');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setTradeAmt($value)
-    {
-        return $this->setParameter('TradeAmt', $value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getTradeDate()
-    {
-        return $this->getParameter('TradeDate');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setTradeDate($value)
-    {
-        return $this->setParameter('TradeDate', $value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getTradeNo()
-    {
-        return $this->getTransactionReference();
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setTradeNo($value)
-    {
-        return $this->setTransactionReference($value);
-    }
-
-    /**
-     * @return string
-     */
-    public function getCheckMacValue()
-    {
-        return $this->getParameter('CheckMacValue');
-    }
-
-    /**
-     * @param  string  $value
-     * @return $this
-     */
-    public function setCheckMacValue($value)
-    {
-        return $this->setParameter('CheckMacValue', $value);
-    }
 
     /**
      * @return array
      *
-     * @throws InvalidRequestException
      * @throws InvalidResponseException
      */
     public function getData()
     {
-        $this->validate('MerchantID', 'CheckMacValue');
+        $data = $this->httpRequest->request->all();
+        $this->setTransactionId($data['MerchantTradeNo']);
+        $this->setTransactionReference($data['TradeNo']);
 
-        return $this->checkMacValue([
-            'CustomField1' => $this->getCustomField1(),
-            'CustomField2' => $this->getCustomField2(),
-            'CustomField3' => $this->getCustomField3(),
-            'CustomField4' => $this->getCustomField4(),
-            'MerchantID' => $this->getMerchantID(),
-            'MerchantTradeNo' => $this->getMerchantTradeNo(),
-            'PaymentDate' => $this->getPaymentDate(),
-            'PaymentType' => $this->getPaymentType(),
-            'PaymentTypeChargeFee' => $this->getPaymentTypeChargeFee(),
-            'RtnCode' => $this->getRtnCode(),
-            'RtnMsg' => $this->getRtnMsg(),
-            'SimulatePaid' => $this->getSimulatePaid(),
-            'StoreID' => $this->getStoreID(),
-            'TradeAmt' => $this->getTradeAmt(),
-            'TradeDate' => $this->getTradeDate(),
-            'TradeNo' => $this->getTransactionReference(),
-            'CheckMacValue' => $this->getCheckMacValue(),
-        ]);
+        return $this->checkMacValue($data);
     }
 
     /**
diff --git a/tests/GatewayTest.php b/tests/GatewayTest.php
index bbf5957..94178ad 100644
--- a/tests/GatewayTest.php
+++ b/tests/GatewayTest.php
@@ -20,21 +20,20 @@ public function setUp(): void
     {
         parent::setUp();
 
+        $this->options = ['testMode' => true];
         $this->gateway = new StubGateway($this->getHttpClient(), $this->getHttpRequest());
+        $this->gateway->initialize($this->options);
+    }
 
-        $this->options = [
+    public function testPurchase()
+    {
+        $response = $this->gateway->purchase([
             'transactionId' => uniqid('MerchantTradeNo', true),
             'amount' => 2000,
             'description' => 'description',
             'returnUrl' => 'https://foo.bar/return_url',
             'notifyUrl' => 'https://foo.bar/notify_url',
-            'testMode' => true,
-        ];
-    }
-
-    public function testPurchase()
-    {
-        $response = $this->gateway->purchase(array_merge($this->options, []))->send();
+        ])->send();
 
         self::assertFalse($response->isSuccessful());
         self::assertTrue($response->isRedirect());
@@ -44,7 +43,7 @@ public function testPurchase()
 
     public function testCompletePurchase()
     {
-        $response = $this->gateway->completePurchase(array_merge($this->options, [
+        $this->getHttpRequest()->request->add([
             'CustomField1' => '',
             'CustomField2' => '',
             'CustomField3' => '',
@@ -62,7 +61,8 @@ public function testCompletePurchase()
             'TradeDate' => '2019/09/02 15:49:16',
             'TradeNo' => '1909021549160081',
             'CheckMacValue' => 'E7EC8DDC6C5C51B1A4D8BEA261246066858B38184C55FD3DD3D6DFF53F535A64',
-        ]))->send();
+        ]);
+        $response = $this->gateway->completePurchase()->send();
 
         self::assertTrue($response->isSuccessful());
         self::assertEquals('Succeeded', $response->getMessage());
@@ -70,7 +70,7 @@ public function testCompletePurchase()
 
     public function testAcceptNotification()
     {
-        $response = $this->gateway->acceptNotification(array_merge($this->options, [
+        $this->getHttpRequest()->request->add([
             'CustomField1' => '',
             'CustomField2' => '',
             'CustomField3' => '',
@@ -88,7 +88,8 @@ public function testAcceptNotification()
             'TradeDate' => '2019/09/02 15:49:16',
             'TradeNo' => '1909021549160081',
             'CheckMacValue' => 'E7EC8DDC6C5C51B1A4D8BEA261246066858B38184C55FD3DD3D6DFF53F535A64',
-        ]))->send();
+        ]);
+        $response = $this->gateway->acceptNotification()->send();
 
         self::assertTrue($response->isSuccessful());
         self::assertEquals('Succeeded', $response->getMessage());
diff --git a/tests/Message/AcceptNotificationRequestTest.php b/tests/Message/AcceptNotificationRequestTest.php
index 75c382e..05d26d7 100644
--- a/tests/Message/AcceptNotificationRequestTest.php
+++ b/tests/Message/AcceptNotificationRequestTest.php
@@ -2,7 +2,6 @@
 
 namespace Omnipay\ECPay\Tests\Message;
 
-use Omnipay\Common\Exception\InvalidRequestException;
 use Omnipay\Common\Exception\InvalidResponseException;
 use Omnipay\Common\Message\NotificationInterface;
 use Omnipay\ECPay\Message\AcceptNotificationRequest;
@@ -11,12 +10,11 @@
 class AcceptNotificationRequestTest extends TestCase
 {
     /**
-     * @throws InvalidRequestException
      * @throws InvalidResponseException
      */
     public function testGetData()
     {
-        $options = [
+        $data = [
             'CustomField1' => '',
             'CustomField2' => '',
             'CustomField3' => '',
@@ -36,18 +34,19 @@ public function testGetData()
             'CheckMacValue' => 'E7EC8DDC6C5C51B1A4D8BEA261246066858B38184C55FD3DD3D6DFF53F535A64',
         ];
 
+        $this->getHttpRequest()->request->add($data);
         $request = new AcceptNotificationRequest($this->getHttpClient(), $this->getHttpRequest());
-        $request->initialize(array_merge([
+        $request->initialize([
             'HashKey' => '5294y06JbISpM5x9',
             'HashIV' => 'v77hoKGq4kWxNNIS',
             'EncryptType' => '1',
             'MerchantID' => '2000132',
-        ], $options));
+        ]);
         $request->setTestMode(true);
 
-        self::assertEquals($options, $request->getData());
+        self::assertEquals($data, $request->getData());
 
-        return [$request, $options];
+        return [$request, $data];
     }
 
     /**
@@ -56,10 +55,10 @@ public function testGetData()
     public function testSendData($results)
     {
         $notification = $results[0];
-        $options = $results[1];
+        $data = $results[1];
 
-        self::assertEquals($options['MerchantTradeNo'], $notification->getTransactionId());
-        self::assertEquals($options['TradeNo'], $notification->getTransactionReference());
+        self::assertEquals($data['MerchantTradeNo'], $notification->getTransactionId());
+        self::assertEquals($data['TradeNo'], $notification->getTransactionReference());
         self::assertEquals(NotificationInterface::STATUS_COMPLETED, $notification->getTransactionStatus());
         self::assertEquals('Succeeded', $notification->getMessage());
         self::assertEquals('1|OK', $notification->getReply());
@@ -70,7 +69,7 @@ public function testInvalidCheckMacValue()
         $this->expectException(InvalidResponseException::class);
         $this->expectExceptionMessage('CheckMacValue verify fail');
 
-        $options = [
+        $data = [
             'CustomField1' => '',
             'CustomField2' => '',
             'CustomField3' => '',
@@ -90,13 +89,14 @@ public function testInvalidCheckMacValue()
             'CheckMacValue' => '7EC8DDC6C5C51B1A4D8BEA261246066858B38184C55FD3DD3D6DFF53F535A64',
         ];
 
+        $this->getHttpRequest()->request->add($data);
         $request = new AcceptNotificationRequest($this->getHttpClient(), $this->getHttpRequest());
-        $request->initialize(array_merge([
+        $request->initialize([
             'HashKey' => '5294y06JbISpM5x9',
             'HashIV' => 'v77hoKGq4kWxNNIS',
             'EncryptType' => '1',
             'MerchantID' => '2000132',
-        ], $options));
+        ]);
         $request->setTestMode(true);
         $request->send();
     }
diff --git a/tests/Message/CompletePurchaseRequestTest.php b/tests/Message/CompletePurchaseRequestTest.php
index ee84c50..d01418c 100644
--- a/tests/Message/CompletePurchaseRequestTest.php
+++ b/tests/Message/CompletePurchaseRequestTest.php
@@ -2,7 +2,6 @@
 
 namespace Omnipay\ECPay\Tests\Message;
 
-use Omnipay\Common\Exception\InvalidRequestException;
 use Omnipay\Common\Exception\InvalidResponseException;
 use Omnipay\ECPay\Message\CompletePurchaseRequest;
 use Omnipay\Tests\TestCase;
@@ -10,12 +9,11 @@
 class CompletePurchaseRequestTest extends TestCase
 {
     /**
-     * @throws InvalidRequestException
      * @throws InvalidResponseException
      */
     public function testGetData()
     {
-        $options = [
+        $data = [
             'CustomField1' => '',
             'CustomField2' => '',
             'CustomField3' => '',
@@ -35,18 +33,19 @@ public function testGetData()
             'CheckMacValue' => 'E7EC8DDC6C5C51B1A4D8BEA261246066858B38184C55FD3DD3D6DFF53F535A64',
         ];
 
+        $this->getHttpRequest()->request->add($data);
         $request = new CompletePurchaseRequest($this->getHttpClient(), $this->getHttpRequest());
-        $request->initialize(array_merge([
+        $request->initialize([
             'HashKey' => '5294y06JbISpM5x9',
             'HashIV' => 'v77hoKGq4kWxNNIS',
             'EncryptType' => '1',
             'MerchantID' => '2000132',
-        ], $options));
-        $request->setTestMode(true);
+            'testMode' => true,
+        ]);
 
-        self::assertEquals($options, $request->getData());
+        self::assertEquals($data, $request->getData());
 
-        return [$request->send(), $options];
+        return [$request->send(), $data];
     }
 
     /**
@@ -55,13 +54,13 @@ public function testGetData()
     public function testSendData($result)
     {
         $response = $result[0];
-        $options = $result[1];
+        $data = $result[1];
 
         self::assertTrue($response->isSuccessful());
         self::assertEquals('Succeeded', $response->getMessage());
-        self::assertEquals($options['RtnCode'], $response->getCode());
-        self::assertEquals($options['TradeNo'], $response->getTransactionReference());
-        self::assertEquals($options['MerchantTradeNo'], $response->getTransactionId());
+        self::assertEquals($data['RtnCode'], $response->getCode());
+        self::assertEquals($data['TradeNo'], $response->getTransactionReference());
+        self::assertEquals($data['MerchantTradeNo'], $response->getTransactionId());
     }
 
     public function testInvalidCheckMacValue()
@@ -69,7 +68,7 @@ public function testInvalidCheckMacValue()
         $this->expectException(InvalidResponseException::class);
         $this->expectExceptionMessage('CheckMacValue verify fail');
 
-        $options = [
+        $data = [
             'CustomField1' => '',
             'CustomField2' => '',
             'CustomField3' => '',
@@ -89,14 +88,15 @@ public function testInvalidCheckMacValue()
             'CheckMacValue' => '7EC8DDC6C5C51B1A4D8BEA261246066858B38184C55FD3DD3D6DFF53F535A64',
         ];
 
+        $this->getHttpRequest()->request->add($data);
         $request = new CompletePurchaseRequest($this->getHttpClient(), $this->getHttpRequest());
-        $request->initialize(array_merge([
+        $request->initialize([
             'HashKey' => '5294y06JbISpM5x9',
             'HashIV' => 'v77hoKGq4kWxNNIS',
             'EncryptType' => '1',
             'MerchantID' => '2000132',
-        ], $options));
-        $request->setTestMode(true);
+            'testMode' => true,
+        ]);
 
         $request->send();
     }