Acumatica API not returning a field value

Hi,

I’m using Acumatica API in a C# project. I wrote following code to access all the Purchase Receipts:

if (InitAPI() == false) { return ""; }
                PO302000Content POReceipt = context.PO302000GetSchema();
                #region Fields
                List<Command> cmdSelect = new List<Command>();
                cmdSelect.Add(POReceipt.DocumentSummary.ReceiptNbr);
                cmdSelect.Add(POReceipt.DocumentSummary.VendorRef);
                cmdSelect.Add(POReceipt.DocumentSummary.Status);
                cmdSelect.Add(POReceipt.DocumentSummary.ExternalNbr);
                cmdSelect.Add(POReceipt.Other.Branch);
                cmdSelect.Add(POReceipt.Other.BillDate);
                cmdSelect.Add(POReceipt.Other.INRefNbr);
                cmdSelect.Add(POReceipt.Details.InventoryID);
                Field lmd = new Field
                {
                    ObjectName = POReceipt.DocumentSummary.ReceiptNbr.ObjectName,
                    FieldName = "LastModifiedDateTime"
                };
                cmdSelect.Add(lmd);
                Field cdt = new Field
                {
                    ObjectName = POReceipt.DocumentSummary.ReceiptNbr.ObjectName,
                    FieldName = "CreatedDateTime"
                };
                cmdSelect.Add(cdt);
                #endregion Fields

                #region Filters
                List<Filter> filters = new List<Filter>();
                filters.Add(new Filter()
                {
                    Field = new Field
                    {
                        ObjectName = POReceipt.DocumentSummary.ReceiptNbr.ObjectName,
                        FieldName = "CreatedDateTime"
                    },
                    Condition = FilterCondition.GreaterOrEqual,
                    Value = DateTime.Now.AddDays(-1).ToLongDateString(),
                    Operator = FilterOperator.And
                });

                #endregion Filters

                var POReceiptExport = context.PO302000Export(cmdSelect.ToArray(), filters.ToArray(), 0, false, false);
                foreach (var dd in POReceiptExport)
                {
                    
                }

I’m getting all the field values correctly except INRefNbr.  Which is showing me a blank value. I checked all the PO Receipts are in released status and have a value in this field at screen. Any idea why I’m not getting this field value and how to resolve that? would really appreciate your help..