Mistakes do happen in life. But, if you have made an accidental mistakenly payment on PayPal then it might have serious consequences. Why? Because you can't cancel a PayPal payment that has completed. On the other hand, if the status of your accidental payment is pending then you can cancel a PayPal transfer. It is good to know the simple step by step process to abort a transaction on PayPal that has not completed. Learn more about how do I cancel a PayPal Payment?