ZenLedger does not store any sensitive information in your account, including your payment method. For this reason, it is not possible to make edits to your payment method, as we use a third-party application to process payment. We do however have a yearly auto-renew of subscriptions, which users are automatically signed up for when they first purchase a plan. You can read more about this in our Auto-Renew Article.
If you would like to cancel auto-renewal in your account in order to purchase a plan with a different payment method than you have used in the past, you will find instructions in that article on how to do so.