elasticsearch-net: expected:'"', actual:' ', at offset:61: UnexpectedElasticsearchClientException

NEST/Elasticsearch.Net version: 7.6.1

Elasticsearch version: 7.1

Description of the problem including expected versus actual behavior: Getting UnexpectedElasticsearchClientException on sequantial requests match_all rests.

expected:‘"’, actual:’ ', at offset:61: UnexpectedElasticsearchClientException at Elasticsearch.Net.Transport1.RequestAsync[TResponse](HttpMethod method, String path, CancellationToken cancellationToken, PostData data, IRequestParameters requestParameters) at Nest.ElasticClient.SearchAsync[TDocument](ISearchRequest request, CancellationToken ct) at Nest.ElasticClient.SearchAsync[TDocument](Func2 selector, CancellationToken ct) at GlobalSearch.Infrastructure.Helpers.DefaultNestSearchExecutor.Search[T](ValueTuple`8 searchParams) in C:_agents\r\r001_work\7\s\src\globalsearch\Infrastructure\Helpers\DefaultNestSearchExecutor.cs:line 49 at GlobalSearch.Services.SearchProcessor.SearchObjectDetails(SearchRequestDto request) in C:_agents\r\r001_work\7\s\src\globalsearch\Services\SearchProcessor.cs:line 46 at GlobalSearch.Handlers.SearchProxyHandler(SearchRequestDto request, ILambdaContext context) in C:_agents\r\r001_work\7\s\src\globalsearch\Handlers.cs:line 26 at lambda_method(Closure , Stream , Stream , LambdaContextInternal )

at Elasticsearch.Net.Utf8Json.JsonReader.ReadStringSegmentRaw() at Deserialize(Object[] , JsonReader& , IJsonFormatterResolver ) at Elasticsearch.Net.Utf8Json.Resolvers.DynamicMethodAnonymousFormatter1.Deserialize(JsonReader& reader, IJsonFormatterResolver formatterResolver) at Elasticsearch.Net.Utf8Json.JsonSerializer.Deserialize[T](Byte[] bytes, Int32 offset, IJsonFormatterResolver resolver) at Elasticsearch.Net.Utf8Json.JsonSerializer.DeserializeAsync[T](Stream stream, IJsonFormatterResolver resolver) at Elasticsearch.Net.ResponseBuilder.SetBodyAsync[TResponse](ApiCallDetails details, RequestData requestData, Stream responseStream, String mimeType, CancellationToken cancellationToken) at Elasticsearch.Net.ResponseBuilder.ToResponseAsync[TResponse](RequestData requestData, Exception ex, Nullable1 statusCode, IEnumerable1 warnings, Stream responseStream, String mimeType, CancellationToken cancellationToken) at Elasticsearch.Net.HttpConnection.RequestAsync[TResponse](RequestData requestData, CancellationToken cancellationToken) at Elasticsearch.Net.RequestPipeline.CallElasticsearchAsync[TResponse](RequestData requestData, CancellationToken cancellationToken) at Elasticsearch.Net.Transport1.RequestAsync[TResponse](HttpMethod method, String path, CancellationToken cancellationToken, PostData data, IRequestParameters requestParameters)

on match_all request after a sequential set of same requests.

Steps to reproduce:

1. Start to execute the same heavy requests.
2. After some time app starts to fire UnexpectedElasticsearchClientException.

Expected behavior A clear and concise description of what you expected to happen. Expected not to receive UnexpectedElasticsearchClientException.

Provide ConnectionSettings (if relevant):

Provide DebugInformation (if relevant):