protected function build()
    {
        $operation = $this->buildOperation('DeleteProfile');

        $merchantID = $this->document->createElement(
            'merchantID',
            $this->merchantId
        );
        $operation->appendChild($merchantID);

        $customerId = $this->document->createElement(
            'customerID',
            $this->customerId
        );
        $operation->appendChild($customerId);

        if ($this->profileId) {
            $profileId = $this->document->createElement(
                'profileID',
                $this->profileId
            );
            $operation->appendChild($profileId);
        }
    }