A customer orders two shirts and one jacket in B2C Commerce.

The object that is created and linked to the Order Summary when a customer cancels an order prior to fulfillment is Cancel Order. A Cancel Order is a record that represents a cancellation request for an order or part of an order. A Cancel Order has a lookup relationship to both Order Summary and Change Order objects, and it contains information such as the cancellation reason, status, date, etc. Verified References:https://help.salesforce.com/s/articleView?id=sf.order_management_cancel_order.htm &type=5