Yes, the default hikashop coupon system eliminates the coupon box after a coupon has been accepted, but if you have the awocoupon plugin enabled, it should automatically keep it open. Worst case scenario you can create an override of the coupon code.
copy the file
www/components/com_hikashop/views/checkout/tmpl/coupon.php
to the below (if it does not exist already)
www/templates/[YOUR_TEMPLATE]/html/com_hikashop/checkout/coupon.php
Then in the template file, remove the if statement. So the code should go from
<?php
if(empty($this->coupon)){
echo JText::_('HIKASHOP_ENTER_COUPON');
?>
<input id="hikashop_checkout_coupon_input" type="text" name="coupon" value="" />
<?php
echo $this->cart->displayButton(JText::_('ADD'),'refresh',$this->params,hikashop_completeLink('checkout'),'',' onclick="return hikashopCheckCoupon(\'hikashop_checkout_coupon_input\');"');
}else{
echo JText::sprintf('HIKASHOP_COUPON_LABEL',@$this->coupon->discount_code);
global $Itemid;
$url_itemid='';
if(!empty($Itemid)){
$url_itemid='&Itemid='.$Itemid;
}
?>
<a href="<?php echo hikashop_completeLink('checkout&task=step&step='.($this->step+1).'&previous='.$this->step.'&removecoupon=1'.'&'.JUtility::getToken().'=1'.$url_itemid); ?>" title="<?php echo JText::_('REMOVE_COUPON'); ?>" >
<img src="<?php echo HIKASHOP_IMAGES . 'delete2.png';?>" alt="<?php echo JText::_('REMOVE_COUPON'); ?>" />
</a>
<?php }?>
to
<?php
echo JText::_('HIKASHOP_ENTER_COUPON');
?>
<input id="hikashop_checkout_coupon_input" type="text" name="coupon" value="" />
<?php
echo $this->cart->displayButton(JText::_('ADD'),'refresh',$this->params,hikashop_completeLink('checkout'),'',' onclick="return hikashopCheckCoupon(\'hikashop_checkout_coupon_input\');"');
echo JText::sprintf('HIKASHOP_COUPON_LABEL',@$this->coupon->discount_code);
global $Itemid;
$url_itemid='';
if(!empty($Itemid)){
$url_itemid='&Itemid='.$Itemid;
}
?>
<a href="<?php echo hikashop_completeLink('checkout&task=step&step='.($this->step+1).'&previous='.$this->step.'&removecoupon=1'.'&'.JUtility::getToken().'=1'.$url_itemid); ?>" title="<?php echo JText::_('REMOVE_COUPON'); ?>" >
<img src="<?php echo HIKASHOP_IMAGES . 'delete2.png';?>" alt="<?php echo JText::_('REMOVE_COUPON'); ?>" />
</a>
