How can we achieve the following Late Charges calculation for the our business scenario

How can we achieve the following Late Charges calculation for the our business scenario whereby for example:
Invoice due on 15th July, customer has a 7days grace day period (hence expecting customer's payment to be made to us on or before 22 July). When the payment is received on 23 July, when we run the late charges on 31st July, we would like to calculate the late interest from the invoice due date until the date when we received the payment i.e. 15th July to 23 July.

From our understanding and testing, with the above scenario, currently Oracle behaviour is the late charges will not be calculated anymore when we run it on 31 July, as the invoice has been paid.