Unable to match predicate of path and value for grpc request

Question

I am using the grpc plugin to create stubs for grpc requests. It works very well when matching the path only. However, I am facing issues to match both the path and the value. In particular, I am using the jsonpath to select the fields to match. Here is a sample o the request:

{
  "path": "/service.DataProvider/ReadData",
  "value": {
    "identifiers": [
      {
        "unique_id": "unset",
        "data_id": "point1",
        "system_id": "mock"
      }
    ],
    "start_time": {
      "seconds": "1650431509",
      "nanos": 0
    },
    "end_time": {
      "seconds": "1650431569",
      "nanos": 0
    }
  }
}

and the predicates:

        "predicates": [
        {
            "deepEquals": {
              "path": "/service.DataProvider/ReadData"
            }
          },
          {
            "jsonpath": {
              "selector": "$.identifiers[0].data_id"
            },
            "deepEquals": {
              "value": "point1"
            }
          },
          {
            "jsonpath": {
              "selector": "$.identifiers[0].system_id"
            },
            "deepEquals": {
              "value": "mock"
            }
          }
        ]

Any idea of what is wrong on the predicates above? Any comments will be highly appreciated. Thanks!