Hi,
Your tech person has added custom CSS to the file
www.lightheartgear.com/templates/yoo_vid...orange/css/theme.css
of your template in order to remove the stock display on the product page:
span.hikashop_product_stock_count, .hika_address_field .hika_edit {display:none !important}
This removes both the stock and the no stock message.
What you can do is add after that code, the code:
.hikashop_product_no_stock{ display: block ! important; }
which should supercede the CSS rule of your tech person and keep the stock hidden, but display the no stock message.