You can do this yourself very quickly and easily! :) We have recently added a new section  where you can make the payment(s) for your missed payment(s) from within your account.

If you go to "Inonebox", which you can access via the menu in your account, you will see at the bottom of the page detailed payment information, including which months you have paid (Paid) and which payment(s) failed (Chargeback). By clicking on the 'Pay' button next to the failed invoice(s), you will be automatically directed to your payment environment.

Once you have made your payment, this will be visible in your account within a matter of seconds. You might have to refresh your web browser ;)

Unfortunately it is not yet possible to pay in one go for multiple invoices that have not yet been paid.