update value from different xml node using XSLT if in SAP CPI

I have some trouble for update value using if on XSLT from other reference element.

D_3035 field value SU should be available and populated.
D_3055 field value should be 92 from 9.

But all other BY/CA/ST on D3035 was impact and changed all value 92 on D_3055

Would you be able to provide XSLT code review and let us know?

Source XML

 <G_SG2>
      <S_NAD>
         <D_3035>CA</D_3035>
         <C_C082>
            <D_3039>MYCARRIER</D_3039>
            <D_3055>92</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>BY</D_3035>
         <C_C082>
            <D_3039>0000152055</D_3039>
            <D_3055>9</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>ST</D_3035>
         <C_C082>
            <D_3039>0000152055</D_3039>
            <D_3055>9</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>SU</D_3035>
         <C_C082>
            <D_3039>3000</D_3039>
            <D_3055>9</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>

XSLT

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output method="xml" indent="yes"/>

 <xsl:template match="@* | node()">
     <xsl:copy>
         <xsl:apply-templates select="@* | node()"/>
     </xsl:copy>
 </xsl:template>

<xsl:variable name="varD_3035" select="//D_3035"/>
<xsl:variable name="varD_3055" select="//D_3055"/>

<xsl:template match="D_3055">
<D_3055>
        <xsl:value-of select= "if( $varD_3035 = 'SU' ) then '92'  else $varD_3055 "/>
</D_3055>
</xsl:template>
</xsl:stylesheet>

incorrect xml

all 92 was populated on D_3035

   <G_SG2>
      <S_NAD>
         <D_3035>CA</D_3035>
         <C_C082>
            <D_3039>MYCARRIER</D_3039>
            <D_3055>92</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>BY</D_3035>
         <C_C082>
            <D_3039>0000152055</D_3039>
            <D_3055>92</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>ST</D_3035>
         <C_C082>
            <D_3039>0000152055</D_3039>
            <D_3055>92</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>SU</D_3035>
         <C_C082>
            <D_3039>3000</D_3039>
            <D_3055>92</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>

I run XSLT several times but it is same.

I am expecting XML as below:

   <G_SG2>
      <S_NAD>
         <D_3035>CA</D_3035>
         <C_C082>
            <D_3039>MYCARRIER</D_3039>
            <D_3055>9</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>BY</D_3035>
         <C_C082>
            <D_3039>0000152055</D_3039>
            <D_3055>9</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>ST</D_3035>
         <C_C082>
            <D_3039>0000152055</D_3039>
            <D_3055>9</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>
   <G_SG2>
      <S_NAD>
         <D_3035>SU</D_3035>
         <C_C082>
            <D_3039>3000</D_3039>
            <D_3055>92</D_3055>
         </C_C082>
      </S_NAD>
   </G_SG2>

Solution

It seems

 <xsl:template match="@* | node()">
     <xsl:copy>
         <xsl:apply-templates select="@* | node()"/>
     </xsl:copy>
 </xsl:template>


<xsl:template match="S_NAD[D_3035 = 'SU']//D_3055">
  <xsl:copy>92</xsl:copy>
</xsl:template>

might express your requirement (although the formulation is not clear to me).

And I don't know why, in the wanted result, you have

 <S_NAD>
     <D_3035>CA</D_3035>
     <C_C082>
        <D_3039>MYCARRIER</D_3039>
        <D_3055>9</D_3055>
     </C_C082>
  </S_NAD>

as the input has

  <S_NAD>
     <D_3035>CA</D_3035>
     <C_C082>
        <D_3039>MYCARRIER</D_3039>
        <D_3055>92</D_3055>
     </C_C082>
  </S_NAD>