Solved
Oct21 ,
Here is the new script assertion for the attached xml
assert context.response
def getData = { data, element ->
new XmlSlurper().parseText(data).'**'.find {it.name() == element}
}
def receiptId = getData(context.response, 'ReceiptId')
log.info receiptId
context.testCase.setPropertyValue('ID', receiptId.toString())