Error in UseOneAsMany Function Error in SAP XI

Error in UseOneAsMany Function Error in SAP XI

Hi Experts,

I am trying the Example of function UseOneAsMany. My Input and Output XML Files are provided below:
<?xml version="1.0" encoding="UTF-8"?>

<ns0:MT_MM4 xmlns:ns0="http://test/mapping.test">
   <Header>
      <MatNo>MatNo</MatNo>
      <MatDesc>MatDesc</MatDesc>
   </Header>
   <Item>
      <MatNo>MatNo1</MatNo>
      <ItemNo>ItemNo1</ItemNo>
      <MatGroup>MatGroup1</MatGroup>
      <Mattype>Mattype1</Mattype>
      <Plant>Plant1</Plant>
   </Item>
   <Item>
      <MatNo>MatNo2</MatNo>
      <ItemNo>ItemNo2</ItemNo>
      <MatGroup>MatGroup2</MatGroup>
      <Mattype>Mattype2</Mattype>
      <Plant>Plant2</Plant>
   </Item>
</ns0:MT_MM4>

My Expected Output should be :

<?xml version="1.0" encoding="UTF-8"?>
-<ns0:MT_MM4R xmlns:ns0="http://test/mapping.test">
-<Header>
<MatNo>MatNo</MatNo>
<MatDesc>MatDesc</MatDesc>
<MatGroup>MatGroup1</MatGroup>
</Header>
-<Item>
<MatNo>MatNo1</MatNo>
<ItemNo>ItemNo1</ItemNo>
<Mattype>Mattype1</Mattype>
<Plant>Plant1</Plant>
</Item>
-<Header>
<MatNo>MatNo</MatNo>
<MatDesc>MatDesc</MatDesc>
<MatGroup>MatGroup2</MatGroup>
</Header>
-<Item>
<MatNo>MatNo2</MatNo>
<ItemNo>ItemNo2</ItemNo>
<Mattype>Mattype2</Mattype>
<Plant>Plant2</Plant>
</Item>
</ns0:MT_MM4R>

But for me Headers are coming first and then followed by two items. Please let me know how to solve the issue and also please provide the explanation.

Thanks,
GIRIDHAR