Database structure for advance/due payment

Question

My frontend program is WPF and SQL Server is backend.

 

I had created a billing application with payment module and whenever user make payment, it should be cleared invoice wise. Now there is an addition to that module, below is the given requirement

 

Customer had some due bills like

customerID = 24

InvoiceNo = 5  = Rs 2000

InvoiceNo = 6 = Rs. 3000

InvoiceNo = 15 = Rs. 4000

InvoiceNo = 26 = Rs.  1000

 

Now customer wants to clear its total bill by giving a cheque of Rs. 10000 (i.e a bulk payment to clear all his dues),

 

In addition to above, customer also advances the amount in regard of invoice amounts like for the above case, customer paid a amount of Rs. 15000 (i.e Rs 5000 advance) that's also want to show to user.

 

Here's is the current payment structure that clears the payment invoice wise

 

Output for the user is showing as below

 

Kindly suggest, how to append the above requirement with the current scenario.