techy - 2014-05-01

I am working on creating HL7 VXU V04 type message using NHapi V2.5.
Below is the required message outcome( from NIST site:http://hl7v2-iz-testing.nist.gov/mu-immunization/)

The issue I am running into is how to create four OBX segments("NHapi.Model.V25.Segment.OBX ") and add it to the "NHapi.Model.V25.Group.VXU_V04_ORDER" ?

Below is my code, Line#5 works, it create multiple ORDER but if i try to do the same to create multiple OBSERVATION (Line#8), I get the below error:
"Can't create repetition #1 of Structure OBSERVATION - this Structure is non-repeating"

As per HL7 specifications OBSERVATION is repeating structure, Anyone please help here?

Any pointers or any suggestions are greatly appreciated.

NHapi.Model.V25.Message.VXU_V04 vxuMsg = new VXU_V04();
PipeParser parser = new PipeParser();
for (int i = 0; i < person.Immunizations.Count; i++)
{
NHapi.Model.V25.Group.VXU_V04_ORDER orc = (NHapi.Model.V25.Group.VXU_V04_ORDER)vxuMsg.GetStructure("ORDER", i);
      for (int j = 0; j < 2; j++)
      {
           NHapi.Model.V25.Group.VXU_V04_OBSERVATION observation = (NHapi.Model.V25.Group.VXU_V04_OBSERVATION)orc.GetStructure("OBSERVATION", j);
NHapi.Model.V25.Segment.OBX obx1 = (NHapi.Model.V25.Segment.OBX)obx.GetStructure("OBX");
       }
     NHapi.Model.V25.Segment.RXA im = orc.RXA;
     NHapi.Model.V25.Segment.ORC oc = orc.ORC;
     NHapi.Model.V25.Segment.RXR rxr = orc.RXR;
}

Required message outcome 

   MSH|^~\&|Test EHR Application|X68||NIST Test Iz Reg|201207010822||VXU^V04^VXU_V04|NIST-IZ-001.00|P|2.5.1|||AL|ER
PID|1||D26376273^^^NIST MPI^MR||Snow^Madelynn^Ainsley^^^^L|Lam^Morgan|20070706|F||2076-8^Native Hawaiian or Other Pacific Islander^CDCREC|32 Prescott Street Ave^^Warwick^MA^02452^USA^L||^PRN^PH^^^657^5558563|||||||||2186-5^non Hispanic or Latino^CDCREC
PD1|||||||||||02^Reminder/Recall - any method^HL70215|||||A|20120701|20120701
NK1|1|Lam^Morgan^^^^^L|MTH^Mother^HL70063|32 Prescott Street Ave^^Warwick^MA^02452^USA^L|^PRN^PH^^^657^5558563
ORC|RE||IZ-783274^NDA|||||||I-23432^Burden^Donna^A^^^^^NIST-AA-1||57422^RADON^NICHOLAS^^^^^^NIST-AA-1^L
RXA|0|1|20120814||140^Influenza, seasonal, injectable, preservative free^CVX|0.5|mL^MilliLiter [SI Volume Units]^UCUM||00^New immunization record^NIP001|7832-1^Lemon^Mike^A^^^^^NIST-AA-1|^^^X68||||Z0860BB|20121104|CSL^CSL Behring^MVX|||CP|A
RXR|C28161^Intramuscular^NCIT|LD^Left Arm^HL70163
OBX|1|CE|64994-7^Vaccine funding program eligibility category^LN|1|V05^VFC eligible - Federally Qualified Health Center Patient (under-insured)^HL70064||||||F|||20120701|||VXC40^Eligibility captured at the immunization level^CDCPHINVS
OBX|2|CE|30956-7^vaccine type^LN|2|88^Influenza, unspecified formulation^CVX||||||F
OBX|3|TS|29768-9^Date vaccine information statement published^LN|2|20120702||||||F
OBX|4|TS|29769-7^Date vaccine information statement presented^LN|2|20120814||||||F