我希望从请求的响应正文中获取请求编号

[
  {
    "$id": "1",
    "$type": "Op.Request, Op",
    "RequestNumber": "2022.06145",
    "WorkTitle": "Title",
    "Status": null,
    "StatusCode": "NEW",
    "Substatus": null,
    "PriorityCode": "MED",
    "Priority": null,
    "WorkflowManager": null,
    "WorkflowManagerId": null,
    "RequestDescription": null,
    "CorporateBodyCode": "PUBL",
    "CorporateBody": null,

这是我的设定

json response body Image
Debug image
我是不是忘了什么？
期望获取变量的值，但获取的是空值