Often, the complete order isn’t returned and therefore you can choose whether to credit the complete invoice, or to only credit a part of it. You can also adjust the amount of the invoice for any reason.
If the complete order is returned, you should use the CreditInvoice request to make a full return.
Maybe the most common situation - not everything's returned - and therefore you shouldn't credit the complete order but instead only the returned invoice rows. This is done using the PartCreditInvoice.
To adjust the amount of the invoice, just use the AdjustInvoice function. It’s possible to adjust the amount both negative and positive. Please note that it’s not possible to do a negative adjustment greater than the total amount of the invoice. A positive adjustment can result in additional credit checks being made.
Please note that the StoreId parameter is mandatory to include in the request if you are selling to more than one country or having both consumers and companies as customers. This is used to distinguish between them.