BulkAllResponse and BulkResponse is not giving failed records

I am using a NEST package 7.8.2 and trying to use BulkAll method to insert records batchwiseinto Elasticsearch via C#. When I am disconnecting the Elastic Service during the insert operation I don't see the failed items in the "ItemsWithErrors" property . Moreover BulkResponses and BulkAllResponses just give me the valid responses or a blanket response of 200 or 400 but without the items that got inserted or failed into the elastic. How can I determine that ? Even the "onerror" method does not give us those details