Magento: ปุ่มชำระเงินดำเนินการต่อไม่ได้ดำเนินการขั้นตอนถัดไป

*****
    <div class="buttons-set" id="billing-buttons-container">
        <p class="required"><?php echo $this->__('* Required Fields') ?></p>
        <button type="button" title="<?php echo $this->__('Continue') ?>" class="button" onclick="billing.save()"><span><span><?php echo $this->__('Continue') ?></span></span></button>
        <span class="please-wait" id="billing-please-wait" style="display:none;">
            <img src="<?php echo $this->getSkinUrl('images/opc-ajax-loader.gif') ?>" alt="<?php echo $this->__('Loading next step...') ?>" title="<?php echo $this->__('Loading next step...') ?>" class="v-middle" /> <?php echo $this->__('Loading next step...') ?>
        </span>
    </div>

*****
<script type="text/javascript">
//<![CDATA[
    var billing = new Billing('co-billing-form', '<?php echo $this->getUrl('checkout/onepage/getAddress') ?>address/', '<?php echo $this->getUrl('checkout/onepage/saveBilling') ?>');
    var billingForm = new VarienForm('co-billing-form');

    //billingForm.setElementsRelation('billing:country_id', 'billing:region', '<?php echo $this->getUrl('directory/json/childRegion') ?>', '<?php echo $this->__('Select State/Province...') ?>');
    $('billing-address-select') && billing.newAddress(!$('billing-address-select').value);

    var billingRegionUpdater = new RegionUpdater('billing:country_id', 'billing:region', 'billing:region_id', <?php echo $this->helper('directory')->getRegionJson() ?>, undefined, 'billing:postcode');
//]]>
</script>

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