Create a balance customer invoice and reconcile the payment to the invoice

To create a balance customer invoice,

1. Go to the Sales Order Module and select the relevant Sales Order. Then click on CREATE INVOICE.

2. From here, select "Regular Invoice" and then click CREATE AND VIEW INVOICE. (Make sure deduct down payments field is ticked)

3. Then you will be directed to the invoices list of this particular sales order, here you can select the final invoice which is in the draft status

4.  Now you can update the details (Ex. Invoice Date) and click on CONFIRM

To reconcile payment to Invoice,

1. Go to the relevant feed where the payment has been made. Then click "RECONCILE XX ITEMS". 
2. Find the relevant feed in the list on left the side and search for the counterpart entry through the search bar for the invoice  
3. select the counterpart entry  and click on VALIDATE.

4. Once you validate and go back to the invoice, invoice will be updated with the PAID tag