Add "date due" into an invoice from API SDK

Hi,


I am developing an application to enter an invoice to Peachtree using the API .NET SDK for Sage 50 2013 , and I want to set the date due into the invoice object ( I noted that the property is visible and it can accept a nulleable value) but when I set It a null or not null value (date time), the API throws me the following exception:

System.MissingMethodException was unhandled.

Missing method: 'System.Nullable`1<System.DateTime> Sage.Peachtree.Domain.Entities.Invoice.set_DateDue()'


It seems the 'set method' for date due has not been implemented. By the same way, I tried to load an invoice and get its Date Due but I had the same error.

So, I would like to know, if there is any way to get or set the Date due for an Invoice.

Thanks