Simply follow these steps to change your invoice mail:
Open settings from a computer or tablet.
Click on the "General" tab in the settings menu.
Now change the email in the field called "Invoice email".
Your changes are automatically saved.
Where can I find my old invoices?
Click the payment tab in your settings from a computer or tablet and scroll down for a bit. Here's a button for accessing all your invoices. This article walks you through the process.