If the person you sent money to is on Curve, once the payment is made, it's final and can’t be cancelled.
What if my friend doesn’t have Curve?
If you sent money to someone who doesn’t have Curve and they haven’t yet accepted the transaction, you can cancel it.
To do this, head to the “Send” tab. Tap the ‘bell’ icon in the top left corner, tap the transaction you’d like to cancel. Then, tap “Cancel this payment”. Once cancelled, it will be marked as “Cancelled” in your “Timeline” and under the card you used in the “Wallet” tab.
If your friend doesn't accept the payment, the charge will automatically reverse back to you after 7 days.