Yes, you can apply a payment to an invoice. By default, Express Invoice uses a customer account-based payment. The payment is applied to invoices in the order that they were created.
To apply a payment to a specific invoice, follow these steps:
Click the Payment button on the toolbar
Enter the Date, Customer, Amount, Method and Reference number
In the Applied column of the invoice list, enter the payment next to the correct invoice
Press Tab or Enter to save your change
Click the Record button