使用java使用script更新出现DocumentMissingException

UpdateRequest updateRequest = new UpdateRequest(UdConstant.ES_INDEX, this.ES_TYPE, esId)

                .script(new Script("ctx._source.downloadNum += 1"));

        try {

            UpdateResponse updateResponse = client.update(updateRequest).get();

            System.err.println("ES更新下载次数时返回的status：" + updateResponse.status().getStatus());

        } catch (InterruptedException e) {

            logger.error("ES更新下载次数时出现异常: InterruptedException");

            e.printStackTrace();

        } catch (ExecutionException e) {

            logger.error("ES更新下载次数时出现异常: ExecutionException");

            e.printStackTrace();

        } 

 
官网代码：

UpdateRequest updateRequest = new UpdateRequest("ttl", "doc", "1")

        .script(new Script("ctx._source.gender = \"male\""));

client.update(updateRequest).get();

执行之后出现ExecutionException，
异常信息：
Caused by: RemoteTransportException[[master][127.0.0.1:9300][indices:data/write/update]]; nested: RemoteTransportException[[master][127.0.0.1:9300][indices:data/write/update[s]]]; nested: DocumentMissingException[[resource][undefined]: document missing];
Caused by: RemoteTransportException[[master][127.0.0.1:9300][indices:data/write/update[s]]]; nested: DocumentMissingException[[resource][undefined]: document missing];
Caused by: [unstructured_data/riGHta_STCiWrf_o5ZxgqQ][[unstructured_data][1]] DocumentMissingException[[resource][undefined]: document missing]
 
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