How do they put goods that are out of order online and not stating that? Even after they told me that those goods are not in stock, when I go online to order again they are shown as available

How do they put goods that are out of order online and not stating that? Even after they told me that those goods are not in stock, when I go online to order again they are shown as available. This time I'm not impressed at all, however I'm patiently waiting for my order when I'd available.