Following your agreement on a product return, you should receive a package from the customer. Once you have received that package, you must create a credit slip from the order's page. It can also be called "credit note" or "credit memo".
Credit slips are not created in the "Credit Slips" page , but only listed there. This page is also used to generate a PDF of your credit slips.
Credit Slips Options
There is only one option on the page:
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If you have created a voucher, customers will see it in the "Vouchers" section of their account. If they click on it, it should look something like this:
The amount of the returned item(s) is added to the voucher. The customer can use the discount code (listed in the far left of the column) next time he or she places an order.