The below is my response..
{\"activation\":{\"existing\":false, \"customer\": new}}
Now when I use
testRunner.testCase.get
import groovy.json.JsonSlurper responseContent = testRunner.testCase.getTestStepByName("xxx").getPropertyValue("response") slurperresponse = new JsonSlurper().parseText(responseContent) log.info (slurperresponse.activation.customer)