[GNC] Confused on: Business > Receivable Aging > To Date

[Fran_3]

Looking at Reports > Business > Customer Report
I see a customer had 3 invoices in December of 2018.
Date: 11/13/18 
Due Date 11/13/18Amount: $360.00
Date: 11/13/18 
Due Date 12/15/18Amount: $765.00
Date: 12/28/18
Due Date 1/28/18
Amount: $855.00
And one payment in December of 2018
Date: 12/19/18PaymentAmount: $360.00
Total Dec 2018 Invoices - Total Dec 2018 Payments = $1,620.00
BUT, when I run 
Reports > Business > Receivable Agingand set the "To" Date to either 12/31/18 or 1/1/19
Neither the customer nor the $1,620.00 the owe us appears.
I've experimented with other "To" dates for the Receivable Aging Report but nothing seems to pickup the unpaid amount from the customer.
I guess I don't understand the Aging Report and/or the "To" field so please tell me the error of my ways.
Thanks.