Inventory Planner does not control stock levels and does not act as master of inventory. Inventory levels will be controlled outside of Inventory Planner either by your platform (ie Amazon, Shopify) or by another system like an inventory management system (ie Tradegecko, Brightpearl).
Inventory Planner reads stock levels from your connected platform and updates the information within your Inventory Planner account during a daily data sync.
The only time that Inventory Planner can update stock levels is by optionally pushing received amounts from a purchase order to select sales platform (Shopify, BigCommerce, WooCommerce, Magento, Neto, and Prestashop).