Stage File Action Error occurred while processing activity stageWritesf0.

Summary:

We had a StageFile action to write a file and it was working fine in OIC Gen 2 (and lower environment of OIC GEN3 when we tested it). When our production OIC instance got migrated to GEN3, it is failing with following error message.

Error occurred while processing activity stageWritesf0. Error : Unable to extract schema for operation writesf0 and target Namespace null

Here is the Mapper XSLT
<xsl:template match="/" xml:id="id_11">

          <nstrgmpr:Write xml:id="id_12">

                <nsmpr5:opaqueElement xml:id="id_40">

                      <xsl:value-of select="oraext:encodeReferenceToBase64($GetExtractFile/nsmpr2:executeResponse/nsmpr4:streamReference)" xml:id="id_41"/>

                </nsmpr5:opaqueElement>

          </nstrgmpr:Write>