How to update product description on the checkout and cart for customised products

[jkaiser1]

Hi there, 
Can someone please point me in the right direction as to how I update the highlighted part of the below image (checkout and cart pages) to have it update with the text that the customer has customised it to?

  

[Ugurcan]

ask customer to add the item to the cart again and start over. It is not possible to edit details at checkout unless you are on Shopify Plus