It is not possible to make the refund to an account other than the one from which the payment was made.
What will happen is that the money will be sent to your old bank, which will either make the connection and send the money to your new account or will block the money, saying that it does not know where it should go.
What you should do is contact your old bank and tell them that you are expecting the money to arrive, and when it does, send it to your new account :)
You can also contact us via the help centre so that we can guide you.