We are removing the users from Admin Console based on last activity info.
UI → Admin Console → Members → Click on 3 dots for the user you want to remove → Click on Remove
These users are showing as active (is_active - true) in API response. Please find below the API endpoint.
API endpoint → https://app.asana.com/api/1.0/users?opt_fields=email,is_active,name,resource_type,workspaces
It seems to be a bug. Has anyone encountered this issue?