Zend certified PHP/Magento developer

How to show thanku message only after user submit the popup form in magento 2 until refresh the page

I have contact us buttons more than one in a page. when the user click on the contact us button i am showing the popup form. After user submitting the form i am showing thanku div.But when the user click on contact us button again form is coming. What i need is once the user submitted the form i need to show thanku div only until user refresh the page and also if he click on another contact us button in the same page i need to show thanku div.
How can i achive this.thanku and please correct me if anything wrong in my code

my phtml file



<div id="popup-modal"> 
<div class="contact-form-popup" style="display:none;">

    <form class="form contact"
          action="<?= $block->getUrl("popup/action/index") ?>"
          id="contact-form"
          method="post"
          data-hasrequired="<?= $block->escapeHtmlAttr(__('* Required Fields')) ?>"
          data-mage-init='{"validation":{}}'>
        <fieldset class="fieldset">
            <legend class="legend"><span><?= $block->escapeHtml(__('Get in touch')) ?></span></legend>
            <br/>
            <div class="field note no-label"><?= $block->escapeHtml(__('Simply fill in your details and enquiry below and one of our team will be in touch as soon as possible.')) ?></div>
            <div class="field firstname required">
                <label class="label" for="name"><span><?= $block->escapeHtml(__('Your Name')) ?></span></label>
                <div class="control">
                    <input name="name" id="name" title="<?= $block->escapeHtmlAttr(__('Name')) ?>"
                           class="input-text" type="text" data-validate="{required:true}"/>
                </div>
            </div>
            
            <div class="field emailaddress required">
                <label class="label" for="emailaddress"><span><?= $block->escapeHtml(__('Customer email address')) ?></span></label>
                <div class="control">
                    <input name="emailaddress" id="emailaddress" title="<?= $block->escapeHtmlAttr(__('Email')) ?>"
                           class="input-text" type="email" data-validate="{required:true, 'validate-email':true}"/>
                </div>
            </div>
            <div class="field mobile">
                <label class="label" for="mobile"><span><?= $block->escapeHtml(__('Phone number')) ?></span></label>
                <div class="control">
                    <input name="mobile" id="mobile" title="<?= $block->escapeHtmlAttr(__('Phone number')) ?>"
                           class="input-text" type="text" data-validate="{required:true}"/>
                </div>
            </div>
            <div class="field postcode">
                <label class="label" for="postcode"><span><?= $block->escapeHtml(__('Customer postcode')) ?></span></label>
                <div class="control">
                    <input name="postcode" id="postcode" title="<?= $block->escapeHtmlAttr(__('Customer postcode')) ?>"
                           class="input-text" type="text" data-validate="{required:true}"/>
                </div>
            </div>
            <div class="field enquiry required">
                <label class="label" for="enquiry"><span><?= $block->escapeHtml(__('Enquiry')) ?></span></label>
                <div class="control">
                    <textarea name="enquiry" id="enquiry" title="<?= $block->escapeHtmlAttr(__('Enquiry')) ?>"
                        class="input-text" type="text" data-validate="{required:true}"></textarea>
                </div>
            </div>
            
            <div class="field extension required">
                <input type='hidden' name="extension" id="extension-name"
                       class="input-text" type="text" data-validate="{required:true}"/>
            </div>
        </fieldset>
        <div class="actions-toolbar">
            <div class="primary">
                <button type="submit" id='customer-contact' title="<?= $block->escapeHtmlAttr(__('Submit')) ?>"
                        class="action submit primary">
                    <span><?= $block->escapeHtml(__('Submit')) ?></span>
                </button>
            </div>
        </div>
    </form>
</div>
<div style="display:none" class="static-block-message">
    <legend class="legend"><span><?= $block->escapeHtml(__('Get in touch')) ?></span></legend>
            <br/>
    <div class="field note no-label">
        <?= $block->escapeHtml(__('Simply fill in your details and enquiry below and one of our team will be in touch as soon as possible.')) ?>
    </div>
        <?= $block->escapeHtml(__('Thanku you.A member of our team will be in touch shortly.'))?>
    <div>
</div>
</div>


<script>
require(
    [
        'jquery',
        'Magento_Ui/js/modal/modal'
    ],
    function($, modal) {
        jQuery(document).ready(function(){
            var options = {
                type: 'popup',
                responsive: true,
                innerScroll: true,
                
                buttons: []
            };
            var openModal = modal(options, $('#popup-modal'));

            jQuery('body').on('click', '.demo-banner .pagebuilder-button-primary', function(){
                jQuery('.contact-form-popup').show();
                jQuery('.static-block-message').hide();
                jQuery('#popup-modal').modal('openModal');
            });

            jQuery('body').on('click', '#contact-form .action.submit', function(e){
                e.preventDefault();
                e.stopImmediatePropagation();
                jQuery.ajax({
                    type: 'post',
                    url: '<?php echo $block->getUrl("popup/action/index") ?>',
                    data: jQuery('#contact-form').serialize(),
                    cache: false,
                    showLoader: 'true',
                    success: function(response) {
                        //alert('success');
                        jQuery('.contact-form-popup').hide();
                        jQuery('.static-block-message').show();
                        
                    }
                });
                return false;
            });
        });
    }
);
</script>

my controller file

<?php
namespace TestPopupControllerAction;
 
use ZendLogFilterTimestamp;
use MagentoStoreModelStoreManagerInterface;
use MagentoFrameworkControllerResultFactory; 
 
class Index extends MagentoFrameworkAppActionAction
{
        /**
        * Recipient email config path
        */
        const XML_PATH_EMAIL_RECIPIENT = 'contact/email/recipient_email';
        /**
        * @var MagentoFrameworkMailTemplateTransportBuilder
        */
        protected $_transportBuilder;

        /**
        * @var MagentoFrameworkTranslateInlineStateInterface
        */
        protected $inlineTranslation;

        /**
        * @var MagentoFrameworkAppConfigScopeConfigInterface
        */
        protected $scopeConfig;

        /**
        * @var MagentoStoreModelStoreManagerInterface
        */
        protected $storeManager;
        /**
        * @var MagentoFrameworkEscaper
        */
        protected $_escaper;

        /**
        * @param MagentoFrameworkAppActionContext $context
        * @param MagentoFrameworkMailTemplateTransportBuilder $transportBuilder
        * @param MagentoFrameworkTranslateInlineStateInterface $inlineTranslation
        * @param MagentoFrameworkAppConfigScopeConfigInterface $scopeConfig
        * @param MagentoStoreModelStoreManagerInterface $storeManager
        */
        public function __construct(
            MagentoFrameworkAppActionContext $context,
            MagentoFrameworkMailTemplateTransportBuilder $transportBuilder,
            MagentoFrameworkTranslateInlineStateInterface $inlineTranslation,
            MagentoFrameworkAppConfigScopeConfigInterface $scopeConfig,
            MagentoStoreModelStoreManagerInterface $storeManager,
            MagentoFrameworkEscaper $escaper
        ) {
            parent::__construct($context);
            $this->_transportBuilder = $transportBuilder;
            $this->inlineTranslation = $inlineTranslation;
            $this->scopeConfig = $scopeConfig;
            $this->storeManager = $storeManager;
            $this->_escaper = $escaper;
        }

        /**
         * Post user question
         *
         * @return void
         * @throws Exception
         */
        public function execute()
        {
            $resultRedirect = $this->resultFactory->create(ResultFactory::TYPE_REDIRECT);
            $post = $this->getRequest()->getPostValue();
            //print_r($post);
            //die("hello");
            if (!$post) {
                $this->_redirect('/');
                return;
            }

            $this->inlineTranslation->suspend();

            try {
                $postObject = new MagentoFrameworkDataObject();
                $postObject->setData($post);
                $error = false;

                $sender = [
                    'name' => $this->_escaper->escapeHtml($post['name']),
                    'email' => $this->_escaper->escapeHtml($post['emailaddress']),
                ];

                $storeScope = MagentoStoreModelScopeInterface::SCOPE_STORE; 
                $transport = $this->_transportBuilder
                    ->setTemplateIdentifier('popup_email') // this code we have mentioned in the email_templates.xml
                    ->setTemplateOptions(
                        [
                            'area' => 'frontend',                    
                            'store' => $this->storeManager->getStore()->getId() 
                        ]
                    )
                    ->setTemplateVars([
                        'name' => $post['name'],
                        'email' => $post['emailaddress'],
                        'mobile' => $post['mobile'],
                        'postcode' => $post['postcode'],
                        'enquiry' => $post['enquiry'],

                    ])
                    ->setFrom($sender)
                    ->addTo($this->scopeConfig->getValue(self::XML_PATH_EMAIL_RECIPIENT, $storeScope))
                    ->addTo('mani@gmail.com')
                    -
                    ->getTransport();

                    $transport->sendMessage();
                    $this->inlineTranslation->resume();
                    //$this->messageManager->addSuccess(
                        //__('Thanks for contacting us with your comments and questions. We'll respond to you very soon.')
                    //);
                    //$resultRedirect->setUrl($this->_redirect->getRefererUrl());
                   //$this->_redirect('/');
                    return;
            } catch (Exception $e) {
                $this->inlineTranslation->resume();
                $this->messageManager->addError(__('We can't process your request right now. Sorry, that's all we know.'.$e->getMessage())
                );
                //$resultRedirect->setUrl($this->_redirect->getRefererUrl());

               //$this->_redirect('/');
                return;
            }
        }

}