I am trying to save my custom field data through plugin but it's not working.

**Plugin Class**


    namespace Vendor\Module\Model\Checkout;

    class PaymentInformationManagementPlugin {

        protected $paymentMethodManagement;

        public function __construct(
            \Magento\Quote\Model\QuoteFactory $quote, 
            \Magento\Quote\Api\PaymentMethodManagementInterface $paymentMethodManagement
        ) {
            $this->paymentMethodManagement = $paymentMethodManagement;
            $this->quoteManagement = $quoteManagement;
        }    
    
        public function beforeSavePaymentInformation(
            \Magento\Checkout\Model\PaymentInformationManagement $subject, 
    $cartId, 
            \Magento\Quote\Api\Data\PaymentInterface $paymentInformation
        ) {
            //$paymentInformation->getData('extension_attributes');
            $extenstinAttributes = $paymentInformation->getExtensionAttributes();
            $taxCode = $extenstinAttributes->getTaxCode();
    
            $paymentInformation->setExtensionAttributes($taxCode);
            $this->paymentMethodManagement->set($cartId, $paymentInformation);
    
            return true;
    //        var_dump($taxCode);exit;
    //        $quote=$this->quote->create();
    //        $quote->getPayment()->setData('tax_code',$taxCode);
    //        return $paymentInformation;
        }

    }


extenstion_attribute.xml

    <config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Api/etc/extension_attributes.xsd">
        <extension_attributes for="Magento\Quote\Api\Data\PaymentInterface">
            <attribute code="tax_code" type="string"/>
        </extension_attributes>
    </config>


di.xml

    <config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
        <type name="Magento\Checkout\Model\PaymentInformationManagement">
            <plugin name="save-in-quote-payment" type="Vendor\Module\Model\Checkout\PaymentInformationManagementPlugin" sortOrder="12349"/>
        </type>
    </config>

Can anyone please help me on this.