Sellers who are not using an API integration to manage their store can easily update their stock levels and dis/continue their products through the seller portal.
Access the seller portal here: https://marketplace.mydeal.com.au/
Refer to this guide for updating your stock or discontinuing products via the seller portal: Stock-Update-Instructions.pdf
This guide can also be accessed once logged into the portal. MyDeal recommends that sellers using this method to manage stock and discontinue products, save a copy of the instructions for future reference.