json to xml Error

[omarmaher100]

I got an error when trying to convert json to xml

error is :

{
	"fault": {
		"faultstring": "JSONToXML[JSON-to-XML-3]: Source response is not available",
		"detail": {
			"errorcode": "steps.json2xml.SourceUnavailable"
		}
	}
}

and this the policy

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<JSONToXML async="false" continueOnError="false" enabled="true" name="JSON-to-XML-3">
	<DisplayName>JSON to XML-3</DisplayName>
	<Properties/>
	<Options>
		<NullValue>NULL</NullValue>
		<NamespaceBlockName>#namespaces</NamespaceBlockName>
		<DefaultNamespaceNodeName>$default</DefaultNamespaceNodeName>
		<NamespaceSeparator>:</NamespaceSeparator>
		<TextNodeName>#text</TextNodeName>
		<AttributeBlockName>#attrs</AttributeBlockName>
		<AttributePrefix>@</AttributePrefix>
		<InvalidCharsReplacement>_</InvalidCharsReplacement>
		<ObjectRootElementName>Root</ObjectRootElementName>
		<ArrayRootElementName>Array</ArrayRootElementName>
		<ArrayItemElementName>Item</ArrayItemElementName>
	</Options>
	<OutputVariable>request</OutputVariable>
	<Source>response</Source>
</JSONToXML>