The Klaviyo - Emails category only lists packs when the Klaviyo module is active on your account and Sprwt can reach the template catalogue. Without the module, only the Avery Labels, Meal Containers and Plastic Bags categories appear (a category with no products still shows its heading). To get Klaviyo, buy the Klaviyo add-on on the Addons page or ask support, then connect Klaviyo on the Integrations page.