Error using method saveAll(list) of ElasticsearchRepository and RestHighLevelClient

I used org.elasticsearch:elasticsearch version 6.8 and for connectivity I used TransportClient. I then decided to upgrade to version 7.6 and since TransportClient is Deprecated, I had to use the connection to elastic via the RestHighLevelClient. I'm using a repository to work with an elastic data in springframework. But now I don't have elastic data storage through a repository working. My repository is inherited from the ElasticsearchRepository interface. I use the standard saveAll method.

I have a list of MyPostgresModel and I need to save that into Elastic. I want to do quickly that's why I use @Transactional and use saveAll method with Iterable. MyPostgresModel has toDocument method to return MyElasticModel object.

This is works: myElasticRepository.save(users.get(0).toDocument()); And this isn't works: myElasticRepository.saveAll(() -> users.stream().map(MyPostgresModel::toDocument).iterator());

I have no idea. Why not? That also returns "type is missing;7930: type is missing;7931:.." error. And the debuger tells me that elastic responses "400 Bad Request" status - data validation is not going.

Before I used the TransportClient everything was OK and after all TransportClient and RestHighLevelClient use a common ElasticsearchOperations interface...

I use the following config class for connection:

@Slf4j
@Configuration
@EnableElasticsearchRepositories(basePackages = "com.project.elastic.repository")
public class ElasticConfig extends AbstractElasticsearchConfiguration {

    @Value("${spring.data.elastic.url}")
    private String url;

    @Override
    public RestHighLevelClient elasticsearchClient() {
        return RestClients.create(ClientConfiguration.create(url)).rest();
    }
}

Here is the example of my elastic model:

@Data
@Document(indexName = "user", type = "_doc", createIndex = false)
public class ElasticUser {

    @Id
    private final String id;
    private final String address;
    private final String firstName;
    private final String lastName;
    private final List<String> phones;
    private final String gender;

    public ElasticUser(
            @NonNull String id,
            @NonNull String address,
            @NonNull String firstName,
            @NonNull String lastName,
            @NonNull List<String> phones,
            @Nullable String gender
    ) {
        this.id = id;
        this.address = address;
        this.firstName = firstName;
        this.lastName = lastName;
        this.phones = phones;
        this.gender = gender;
    }
}

Service method:

    @Transactional
    public void saveUsers(@NonNull List<PostgresUser> users) {
//        myElasticRepository.save(users.get(0).toDocument());
        myElasticRepository.saveAll(() -> users.stream().map(PostgresUser::toDocument).iterator());
    }