Error while using transport plugin for Elasticsearch

I get the following error while exporting to Elasticsearch using the transport plugin. What could be the issue?

CapiNozzle 2016-01-15T06:49:01.874Z [ERROR] batchUpdateDocs for vb 369 failed with err Received malformed response from tcp connection vb=369. err=unexpected EOF, num_bytes=300, res_buf={HTTP/1.1 500 MapperParsingException[object mapping for [meta] tried to parse field [null] as object, but got EOF, has a concrete value been provided to it?]

I am using the default template that came with the transport plugin. Some of the Mapper Parsing errors that others have faced is because of the input data. Since the error seems to be in the Meta field, could it still be because of my data?

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