Cancelling a standing order
You can cancel a standing order in the app:
Tap the Payments icon in the menu bar
Tap Scheduled
Tap the payment you want to cancel
Tap Cancel standing order or Cancel scheduled payment
Bear in mind you'll need to cancel a standing order by 23:59 (UTC) the day before the payment is due, otherwise it might still go through. Don't forget to let the recipient know that you've cancelled it, too.