diff --git a/app/uk/gov/hmrc/apiplatformoutboundsoap/services/OutboundService.scala b/app/uk/gov/hmrc/apiplatformoutboundsoap/services/OutboundService.scala
index 9ca2be5..177c753 100644
--- a/app/uk/gov/hmrc/apiplatformoutboundsoap/services/OutboundService.scala
+++ b/app/uk/gov/hmrc/apiplatformoutboundsoap/services/OutboundService.scala
@@ -140,7 +140,7 @@ class OutboundService @Inject()(outboundConnector: OutboundConnector,
   }
 
   private def addHeaders(message: MessageRequest, operation: Operation, envelope: SOAPEnvelope): Unit = {
-    val wsaNs: OMNamespace = getOMFactory.createOMNamespace(WSA_NAMESPACE, "wsa")
+    val wsaNs: OMNamespace = envelope.declareNamespace(WSA_NAMESPACE, "wsa")
     addSoapAction(operation, wsaNs, envelope)
     addMessageHeader(message, operation, envelope)
     addOptionalAddressingHeaders(message, wsaNs, envelope)
@@ -175,10 +175,10 @@ class OutboundService @Inject()(outboundConnector: OutboundConnector,
   }
 
   private def addOptionalAddressingHeaders(message: MessageRequest, wsaNs: OMNamespace, envelope: SOAPEnvelope): Unit = {
-    message.addressing.from.foreach(addToSoapHeader(_, WSA_FROM, wsaNs, envelope))
+    message.addressing.from.foreach(addWithAddressElementChildToSoapHeader(_, WSA_FROM, wsaNs, envelope))
     addToSoapHeader(message.addressing.to, WSA_TO, wsaNs, envelope)
-    addToSoapHeader(message.addressing.replyTo, WSA_REPLY_TO, wsaNs, envelope)
-    message.addressing.faultTo.foreach(addToSoapHeader(_, WSA_FAULT_TO, wsaNs, envelope))
+    addWithAddressElementChildToSoapHeader(message.addressing.replyTo, WSA_REPLY_TO, wsaNs, envelope)
+    message.addressing.faultTo.foreach(addWithAddressElementChildToSoapHeader(_, WSA_FAULT_TO, wsaNs, envelope))
     addToSoapHeader(message.addressing.messageId, WSA_MESSAGE_ID, wsaNs, envelope)
     message.addressing.relatesTo.foreach(addToSoapHeader(_, WSA_RELATES_TO, wsaNs, envelope))
   }
@@ -189,6 +189,14 @@ class OutboundService @Inject()(outboundConnector: OutboundConnector,
     envelope.getHeader.addChild(addressingElement)
   }
 
+  private def addWithAddressElementChildToSoapHeader(property: String, elementName: String, namespace: OMNamespace, envelope: SOAPEnvelope): Unit = {
+    val addressingElement: OMElement = getOMFactory.createOMElement(elementName, namespace)
+    val addressingElementInner: OMElement = getOMFactory.createOMElement("Address", namespace)
+    getOMFactory.createOMText(addressingElementInner, property)
+    addressingElement.addChild(addressingElementInner)
+    envelope.getHeader.addChild(addressingElement)
+  }
+
   private def addBody(message: MessageRequest, operation: Operation, envelope: SOAPEnvelope): Unit = {
     val inputMessageName = operation.getInput.getMessage.getParts.asScala.values.head.asInstanceOf[Part].getElementName
     val payload = getOMFactory.createOMElement(inputMessageName)
diff --git a/test/uk/gov/hmrc/apiplatformoutboundsoap/services/OutboundServiceSpec.scala b/test/uk/gov/hmrc/apiplatformoutboundsoap/services/OutboundServiceSpec.scala
index 8187b75..7091707 100644
--- a/test/uk/gov/hmrc/apiplatformoutboundsoap/services/OutboundServiceSpec.scala
+++ b/test/uk/gov/hmrc/apiplatformoutboundsoap/services/OutboundServiceSpec.scala
@@ -115,21 +115,21 @@ class OutboundServiceSpec extends AnyWordSpec with Matchers with GuiceOneAppPerS
     val expectedStatus: Int = OK
 
     val allAddressingHeaders =
-      """<wsa:From xmlns:wsa="http://www.w3.org/2005/08/addressing">HMRC</wsa:From>
-        |<wsa:To xmlns:wsa="http://www.w3.org/2005/08/addressing">CCN2</wsa:To>
-        |<wsa:ReplyTo xmlns:wsa="http://www.w3.org/2005/08/addressing">ReplyTo</wsa:ReplyTo>
-        |<wsa:FaultTo xmlns:wsa="http://www.w3.org/2005/08/addressing">FaultTo</wsa:FaultTo>
-        |<wsa:MessageID xmlns:wsa="http://www.w3.org/2005/08/addressing">123</wsa:MessageID>
-        |<wsa:RelatesTo xmlns:wsa="http://www.w3.org/2005/08/addressing">RelatesTo</wsa:RelatesTo>""".stripMargin.replaceAll("\n", "")
+      """<wsa:From><wsa:Address>HMRC</wsa:Address></wsa:From>
+        |<wsa:To>CCN2</wsa:To>
+        |<wsa:ReplyTo><wsa:Address>ReplyTo</wsa:Address></wsa:ReplyTo>
+        |<wsa:FaultTo><wsa:Address>FaultTo</wsa:Address></wsa:FaultTo>
+        |<wsa:MessageID>123</wsa:MessageID>
+        |<wsa:RelatesTo>RelatesTo</wsa:RelatesTo>""".stripMargin.replaceAll("\n", "")
 
     val mandatoryAddressingHeaders =
-      """<wsa:To xmlns:wsa="http://www.w3.org/2005/08/addressing">CCN2</wsa:To>
-        |<wsa:ReplyTo xmlns:wsa="http://www.w3.org/2005/08/addressing">ReplyTo</wsa:ReplyTo>
-        |<wsa:MessageID xmlns:wsa="http://www.w3.org/2005/08/addressing">123</wsa:MessageID>""".stripMargin.replaceAll("\n", "")
+      """<wsa:To>CCN2</wsa:To>
+        |<wsa:ReplyTo><wsa:Address>ReplyTo</wsa:Address></wsa:ReplyTo>
+        |<wsa:MessageID>123</wsa:MessageID>""".stripMargin.replaceAll("\n", "")
 
     def expectedSoapEnvelope(extraHeaders: String = ""): String =
       s"""<?xml version='1.0' encoding='utf-8'?>
-         |<soapenv:Envelope xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope">
+         |<soapenv:Envelope xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope" xmlns:wsa="http://www.w3.org/2005/08/addressing">
          |<soapenv:Header>
          |<wsa:Action xmlns:wsa="http://www.w3.org/2005/08/addressing">CCN2.Service.Customs.EU.ICS.RiskAnalysisOrchestrationBAS/IE4N03notifyERiskAnalysisHit</wsa:Action>
          |<ccnm:MessageHeader xmlns:ccnm="http://ccn2.ec.eu/CCN2.Service.Platform.Common.Schema">
@@ -291,8 +291,6 @@ class OutboundServiceSpec extends AnyWordSpec with Matchers with GuiceOneAppPerS
       when(outboundMessageRepositoryMock.persist(*)).thenReturn(Future(InsertOneResult.acknowledged(BsonNumber(1))))
 
       await(underTest.sendMessage(messageRequestMinimalAddressing))
-      getXmlDiff(messageCaptor.getValue.toString, expectedSoapEnvelope(mandatoryAddressingHeaders)).build().getDifferences.forEach(d => println(d))
-
       getXmlDiff(messageCaptor.getValue.toString, expectedSoapEnvelope(mandatoryAddressingHeaders)).build().hasDifferences shouldBe false
     }
 
@@ -304,7 +302,6 @@ class OutboundServiceSpec extends AnyWordSpec with Matchers with GuiceOneAppPerS
       when(outboundMessageRepositoryMock.persist(*)).thenReturn(Future(InsertOneResult.acknowledged(BsonNumber(1))))
 
       await(underTest.sendMessage(messageRequestMinimalAddressing))
-      getXmlDiff(messageCaptor.getValue.toString, expectedSoapEnvelope(mandatoryAddressingHeaders)).build().getDifferences.forEach(d => println(d))
 
       getXmlDiff(messageCaptor.getValue.toString, expectedSoapEnvelope(mandatoryAddressingHeaders)).build().hasDifferences shouldBe false
     }