When you submit someone's email address to send a PayPal payment to them, that email address must be tied with a PayPal account. If there isn't, the payment will be held until the recipient opens an account and accepts the payment, or until 30 days have passed.
If a payment is not accepted within 30 days, it is immediately cancelled and the funds are returned to your account. If the email address you submitted is already associated with a PayPal account, the payment will be accepted and finalised automatically. So, how to cancel a paypal payment