Invalid NEST response built from a successful (404) low level call

Elastic Stack Elasticsearch
2

The response

{"statusCode":404,"error":"Not Found","message":"Not Found"}

looks familiarly like the one in Why does the HTTP authentication with Elasticsearch fail in Rust?.

This doesn't look like a response from Elasticsearch. The Url in the audit trail of http://localhost:5601/ is the default one for Kibana. Are you sending the request to Kibana instead of sending it to Elasticsearch? The default Url for Elasticsearch running locally is http://localhost:9200/