To edit your recurring donation as a donor, go to donorbox.org and log in to your donor account by clicking the Donor Login link at the top of the page. Setting a new password will allow you to setup your donor account.
Once you log in, you can follow these steps:
Click the Active button to the right of the donation plan (or anywhere within the white box for your plan) that you wish to edit.
To change your payment information, click the Payment Method link.
Enter your new payment information, and click Update Card. If the organization has enabled bank transfers on their end, you'll also be able to switch from card payments to bank transfers, and vice versa.
Once that's done, you're all set!