Why can't I reply to a payment or invoice?

It is possible to end up in a state (possibly due to bounced email addresses) where you have no Active contacts on a payment or invoice.

In this state, replies are disabled on the payment's Messages & History page in Routable, because there are no valid contacts available to receive the message.

To resolve this issue and enable replies on your payment or invoice, add a contact to the payment. 

In the payment's Messages & History tab, go to the right sidebar. In the section, Contacts on this payment, click the +Contact button. From there, search for and add an existing contact, or you can create a new contact.

Once a new contact has been added to the payment or invoice, the reply editor will be enabled and you will be able to send a message to the new contact.