Thanks Filippo, direct debit is the correct option to select on the invoice to pay by GoCardless - your customers mandates will appear active on QuickBooks when navigating to the Cog > All lists > Direct debit mandates as long as you are selecting invoices as the transaction type. You can not use this GoCardless set up for sales receipts as these are transactions which you are stating paid straight away and direct debits are payments set up to be paid in the future.