Hi @Tomoyo_Fujita,
Two points:
First, if you’re seeing “Limited Access Member” then that means you’re operating in a workspace as opposed to an organization. In a workspace there’s no concept of any specific email domain, so your part about “specify the email with the same domain as org” is actually not relevant in this case.
Second, I think the addUser API endpoint always adds the person as a Limited Access Member (in a workspace) or as a Guest (in an organization). I don’t know of and have never seen a way to convert someone from a Limited Access Member/Guest to a full member via the API. You can do that in the Admin Console in the Asana web app.