For example, if you executed the transaction for the wrong amount or need to cancel the transaction, you can cancel directly from the application. On the “Payments” tab on the main screen, select the payment you want to cancel and tap on it. The transaction detail is displayed:

At the very bottom, click on the "Cancel transaction" button to cancel the transaction. The application will inform you about the successful cancellation. 

Please note that it is possible to cancel payments not older than 93 days and each transaction can be canceled only once. Currently the transaction can be cancelled for full amount.