ELASTIC SEARCH SERVICE AWS: scroll api do not give me expected response

Question

I am using scroll api to get search results using scroll_id and my request is :

https://my-es-domain-5euba7647rpc35m5utkiwweds.eu-west-1.es.amazonaws.com/_search/scroll?scroll_id=123

The weird thing is that as a response I am getting this:

{
    "took": 1,
    "timed_out": false,
    "_shards": {
        "total": 5,
        "successful": 5,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": 3,
        "max_score": 1,
        "hits": []
    }
}

Is there anything that I am missing here? Why I am not getting the rest of my search results? As you can see hits property is empty.

EDIT: Just to note that when I try to get all results using scroll api then everything is ok:

https://my-es-domain-5euba7647rpc35m5utkiwweds.eu-west-1.es.amazonaws.com/_search?scroll=5m&size=3

{
    "_scroll_id": "123",
    "took": 4,
    "timed_out": false,
    "_shards": {
        "total": 5,
        "successful": 5,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": 3,
        "max_score": 1,
        "hits": [
            {
                "_index": "movies",
                "_type": "movie",
                "_id": "2",
                "_score": 1,
                "_source": {
                    "title": "Lawrence of Arabia",
                    "director": "David Lean",
                    "year": 1962,
                    "genres": [
                        "Adventure",
                        "Biography",
                        "Drama"
                    ]
                }
            },
            {
                "_index": "movies",
                "_type": "movie",
                "_id": "1",
                "_score": 1,
                "_source": {
                    "title": "The Assassination of Jesse James by the Coward Robert Ford",
                    "director": "Andrew Dominik",
                    "year": 2007,
                    "genres": [
                        "Biography",
                        "Crime",
                        "Drama"
                    ]
                }
            },
            {
                "_index": "movies",
                "_type": "movie",
                "_id": "3",
                "_score": 1,
                "_source": {
                    "title": "To Kill a Mockingbird",
                    "director": "Robert Mulligan",
                    "year": 1962,
                    "genres": [
                        "Crime",
                        "Drama",
                        "Mystery"
                    ]
                }
            }
        ]
    }
}

EDIT2: My mistake. When I did first request I was already getting all three results and then when I passed scroll_id as a parameter and tried to get rest of the search results the hits array was empty:)

Answer 1

Maybe you have only 3 documents that match this search? The first scroll returns them, and the second scroll has no more docs to retrieve