Cortex "Error: version conflict, document already exists"

Work Environment

Problem Description

After updating database in Cortex, when the create administrator account pages comes up, nothing happens when I press create after filling up the credentials. I tried refreshing the page but then "Error: user init not found" comes up. The logs show that there is a version conflict, document already exists so tried deleting the Cortex instance and elasticsearch to re-initiate Cortex but still unable to create administrator account. Also tried starting over from the very beginning by installing everything again but still facing the same issue.

Had done this before and everything was working fine until recently.

Steps to Reproduce

1. Install the new instance of Cortex and ElasticSearch

Complementary information

2019-12-03 06:09:34,717 [INFO] from org.thp.cortex.services.ErrorHandler in application-akka.actor.default-dispatcher-5 - POST /api/user returned 400
org.elastic4play.ConflictError: [doc][cortex]: version conflict, document already exists (current version [1])
at org.elastic4play.database.DBConfiguration.$anonfun$execute$2(DBConfiguration.scala:146)
at scala.concurrent.Future.$anonfun$flatMap$1(Future.scala:307)
at scala.concurrent.impl.Promise.$anonfun$transformWith$1(Promise.scala:41)
at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:64)
at akka.dispatch.BatchingExecutor$AbstractBatch.processBatch(BatchingExecutor.scala:55)
at akka.dispatch.BatchingExecutor$BlockableBatch.$anonfun$run$1(BatchingExecutor.scala:91)
at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:23)
at scala.concurrent.BlockContext$.withBlockContext(BlockContext.scala:85)
at akka.dispatch.BatchingExecutor$BlockableBatch.run(BatchingExecutor.scala:91)
at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:40)
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(ForkJoinExecutorConfigurator.scala:44)
at akka.dispatch.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at akka.dispatch.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at akka.dispatch.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at akka.dispatch.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)

Start with the POST /api/user failure and the stack trace location in DBConfiguration.scala:146, then reproduce the fresh Cortex and Elasticsearch installation described in the issue. Trace why the cortex document already exists during administrator creation; done means the administrator account can be created without the version-conflict or subsequent “user init not found” error.