Elasticsearch throw Elasticsearch.Net.UnexpectedElasticsearchClientException - elasticsearch

Question

I have a problem with Elasticsearch.Net.UnexpectedElasticsearchClientException:
I tried change nest edition(eg:5.xxx,2.xxx,6.xxx) and can not fixed this problem,I can't found 7.xxx in nuget,so what should I try again to fixed this?
Exception is:
Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'System.Int64' because the type requires a JSON primitive value (e.g. string, number, boolean, null) to deserialize correctly.
To fix this error either change the JSON to a JSON primitive value (e.g. string, number, boolean, null) or change the deserialized type so that it is a normal .NET type (e.g. not a primitive type like integer, not a collection type like an array or List) that can be deserialized from a JSON object. JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object.
Path 'hits.total.value', line 1, position 115.”
var settings = new ConnectionSettings(new Uri("http://localhost:9200")).DefaultIndex("my-application");
var client = new ElasticClient(settings);
IEnumerable<Person> persons = new List<Person>
{
new Person()
{
Id = "4",
Firstname = "aaa",//Boterhuis-040
Lastname = "Gusto-040",
Chains = new string[]{ "a","b","c" },
},
new Person()
{
Id = "5",
Firstname = "sales#historichousehotels.com",
Lastname = "t Boterhuis 1",
Chains = new string[]{ "a","b","c" },
},
new Person()
{
Id = "6",
Firstname = "Aberdeen #110",
Lastname = "sales#historichousehotels.com",
Chains = new string[]{ "a","b","c" },
},
new Person()
{
Id = "7",
Firstname = "Aberdeen #110",
Lastname = "t Boterhuis 2",
Chains = new string[]{ "a","b","c" },
},
new Person()
{
Id = "8",
Firstname = "Aberdeen #110",
Lastname = "t Boterhuis 2",
Chains = new string[]{ "a","b","c" },
},
};
client.IndexMany<Person>(persons, "test");
var rs = client.Search<Person>(s => s.Index("test"));
var response = rs.Documents;