Using GiftCert on Saleorder created with API

We are synchronizing Netsuite with our existing shopping cart software.  Using the API (2.6), we create a salesorder in NS. 

However, when a customer uses a Gift Certificate as the method of purchase we receive an error, "Gift Certificate Not Found".  We have tried using the Gift Certificate Code as well as the NSKey.

We've tried adding the gift certificate to the salesorder with the following .NET code:

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RecordRef giftCert = new RecordRef();
giftCert.type = RecordType.giftCertificate;
giftCert.typeSpecified = true;
giftCert.internalId = "PGTestGS3";

salesOrder.giftCert = giftCert;

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We can create the salesorder without a Gift Certicate without a problem.

We can also use the Gift Certificate in the Netsuite UI.