I can help you find the appropriate invoices to be paid in the new format, Kjenkyn.
 
Here's how to do it:
 
 - Click + Create in the top left corner.
 
 - Under Customers, select Receive Payment.
 
 - In the Customer field, select the customer whose invoice is being paid.
 
 - Enter the Payment date, Payment method, and Reference no. If applicable.
 
 - In the Deposit to field, select Undeposited Funds.
 
 - Enter the Amount Received that applies to this customer's invoice(s).
 
 - In the Outstanding Transactions section, check the box before the appropriate invoice(s) for this customer.
 
 - Enter the payment amount to split between the selected invoices.
 
 - Click Save and New.
 
 
Additionally, you can refer to this article for an overview of your customers' outstanding balances: Run an accounts receivable ageing report.
 
Feel free to reach out if you have any questions or need assistance with QuickBooks.