If you used a discount voucher on your order and you return the entire order, the discount voucher will be generated again (if its validity date is still current) following the processing of your return in the section “My coupons” from your customer area.
If you used a gift card, following the processing of your return, it will be usable again (with the same code) and visible in your customer area in the "My vouchers and gift cards" section.
If in doubt, do not hesitate to contact our Customer Service.