CustomerPayment, applyList comes back null in production. Why?

I looked all over for docs on this, but found nothing.. I'm trying to initialize a CustomerPayment and then drill into o.applyList.apply in order to get a list of open invoices and amounts due on each for a customer.  Works fine in development environment, but for some reason "applyList" property is null when I take it to production.

Minimal sample code:

        private void button1_Click(object sender, EventArgs e)          {              using (NetSuiteService.NetSuiteService service = new NetSuiteService.NetSuiteService())              {                  service.CookieContainer = new System.Net.CookieContainer();                  Passport passport = new Passport();                  passport.account = "123456"; // From NS login, Support->CustomerService->ContactSupportOnline                  passport.email = "