Subscriptions to Sesami
You are billed on Sesami, like all apps on Shopify, as part of Shopify's 30-day subscription billing period. However, as per the help guide on Shopify, Sesami "has a separate 30-day billing cycle, which impacts the charges you'll see on your Shopify bill."
For more information about how third party apps, like Sesami, are billed in Shopify, please read this handy help guide: https://help.shopify.com/en/manual/your-account/manage-billing/your-invoice/apps