Monetary of currency_sign is empty

My monetary.tpl has smarty php code below:

{if is_numeric($value.value)}{foreach from=$list_currency item="list_currency_item" key="list_currency_key"}{if $list_currency_item.sid == $value.currency}{$list_currency_item.currency_sign}{/if}{/foreach}{tr type="float"}{$value.value}{/tr}{else}{$value.value}{/if}

My search result list is using codes below to show currency sign and Salary value:

[[$listing.Salary.currency_sign]][[$listing.Salary.value]]

My problem is [[$listing.Salary.currency_sign]] always empty value. Any idea?:blush: