When addwish business tracks the items in customers cart, it's possible to associate a unique URL that allows the customer to return to the shop with the specific cart with the items abandoned. If the e-commerce platform of your webshop does not provide the feature of a unique URL to restore a cart, the return to cart button is not displayed.
Note this when previewing and testing
When previewing and testing abandoned cart emails, this page is set as the cart URL (for info purposes). But when sending real and live abandoned cart emails to customers, it will be set accordingly - or if not possible the button is hidden.