you do bad configuration in your warehouse stock location or output location or also product form.

The Stock will be updated after you receive the products:

To receive the products, open "Incoming Products --->Incoming Shipments" and Click on the Red Button "Receive" to confirm the operation.

Yoy can find the "Incoming Products --->Incoming Shipments" menu in Purchases, you can also do the same operation under Warehouse.

After that, and under Warehouse menu, open Internal Moves and move the received products to the location you want.