Is it possible to cancel a shipment without refunding the customer's credit card? We simply wish to get a refund of the store's shipping charge so we can send a package USPS instead. The customer's total payment won't change; we just want to avoid being charged twice for shipping.
First off, if you do not use a shipping label, you will not be charged for the shipment by UPS. If you already processed the order and created the label, then just throw the label away, and UPS will not charge you as they have to scan the label when picked up to charge you. If you have not processed the order yet, then just change the shipping to "No Label" and process the order. Then go to USPS.com and create a shipment.