There are two options for changing a redemption rate for a customer,First option would be giving that customer a special rate or the other or the next option would be

On the Loan Payment Screen, you want to select the loan you are wanting to discount, Once you have done that you want to enter the full overdue amount, then

First you need to select “New Customer” and that will take you to the New Customer Screen, then once you have done that Type in Customers Surname and Date of