Item added in "opening stock" but not visible in "stock summary"

Hello Everyone,

I imported a list of items with the following fields: item name, item group, standard selling rate, supplier, opening stock. The list was successfully imported in the system.

You can see the “opening stock” column in the list. However, when I check the “stock summary” page the items are not listed there. Also, when I open the item page, the “stock level” displays “No stock available”.

Why the “opening stock” number is not displayed as “stock available” ?