Signed-in customers can reorder configured products from their store account. That uses the Appify Reorder block in Checkout and customer accounts — not the product theme.
Shopify’s Buy again button only adds the variant and drops the original configuration. Turn it off, then add Appify Reorder.
The editor preview often hides app extensions. Check the live account page after you save: sign in, open Orders, then open an order.
Whole-order reorder stays in the Appify Reorder block and the order action menu.