java.lang.IllegalArgumentException: DocValuesField "about_this_product_snippet" appears more than once in this document (only one value is allowed per field)
	at org.apache.lucene.index.SortedDocValuesWriter.addValue(SortedDocValuesWriter.java:62)
	at org.apache.lucene.index.DefaultIndexingChain.indexDocValue(DefaultIndexingChain.java:456)
	at org.apache.lucene.index.DefaultIndexingChain.processField(DefaultIndexingChain.java:397)
	at org.apache.lucene.index.DefaultIndexingChain.processDocument(DefaultIndexingChain.java:321)
	at org.apache.lucene.index.DocumentsWriterPerThread.updateDocument(DocumentsWriterPerThread.java:234)
	at org.apache.lucene.index.DocumentsWriter.updateDocument(DocumentsWriter.java:450)
	at org.apache.lucene.index.IndexWriter.updateDocument(IndexWriter.java:1477)
	at com.mantiki.index.Index.buildSource(Index.java:192)
	at com.mantiki.index.Index.build(Index.java:151)
	at com.mantiki.index.daemon.DefaultCatalogueIndexBuildService.updateIndex(DefaultCatalogueIndexBuildService.java:214)
	at com.mantiki.index.daemon.DefaultCatalogueIndexBuildService.updateIndexes(DefaultCatalogueIndexBuildService.java:167)
	at com.mantiki.index.daemon.CatalogueIndexTask.buildIndex(CatalogueIndexTask.java:32)
	at com.mantiki.index.daemon.CatalogueIndexTask.run(CatalogueIndexTask.java:23)
	at com.mantiki.index.daemon.CatalogueIndexTaskExecutor.submitTask(CatalogueIndexTaskExecutor.java:22)
	at com.mantiki.index.daemon.CatalogueIndexTaskExecutor.submitTask(CatalogueIndexTaskExecutor.java:8)
	at com.mantiki.index.daemon.CatalogueIndexTaskCreator.createTasks(CatalogueIndexTaskCreator.java:40)
	at com.mantiki.daemon.TaskCreator.executeTasks(TaskCreator.java:40)
	at com.mantiki.daemon.MantikiDaemon.trigger(MantikiDaemon.java:201)
	at com.mantiki.index.daemon.CatalogueIndexDaemonPollingRunner.start(CatalogueIndexDaemonPollingRunner.java:26)
	at com.mantiki.daemon.MantikiDaemon.run(MantikiDaemon.java:148)
	at java.lang.Thread.run(Thread.java:745)
11:29:33:302 - ERROR - CatalogueIndexTask - Error building index
java.lang.IllegalArgumentException: DocValuesField "about_this_product_snippet" appears more than once in this document (only one value is allowed per field)
	at org.apache.lucene.index.SortedDocValuesWriter.addValue(SortedDocValuesWriter.java:62)
	at org.apache.lucene.index.DefaultIndexingChain.indexDocValue(DefaultIndexingChain.java:456)
	at org.apache.lucene.index.DefaultIndexingChain.processField(DefaultIndexingChain.java:397)
	at org.apache.lucene.index.DefaultIndexingChain.processDocument(DefaultIndexingChain.java:321)
	at org.apache.lucene.index.DocumentsWriterPerThread.updateDocument(DocumentsWriterPerThread.java:234)
	at org.apache.lucene.index.DocumentsWriter.updateDocument(DocumentsWriter.java:450)
	at org.apache.lucene.index.IndexWriter.updateDocument(IndexWriter.java:1477)
	at com.mantiki.index.Index.buildSource(Index.java:192)
	at com.mantiki.index.Index.build(Index.java:151)
	at com.mantiki.index.daemon.DefaultCatalogueIndexBuildService.updateIndex(DefaultCatalogueIndexBuildService.java:214)
	at com.mantiki.index.daemon.DefaultCatalogueIndexBuildService.updateIndexes(DefaultCatalogueIndexBuildService.java:167)
	at com.mantiki.index.daemon.CatalogueIndexTask.buildIndex(CatalogueIndexTask.java:32)
	at com.mantiki.index.daemon.CatalogueIndexTask.run(CatalogueIndexTask.java:23)
	at com.mantiki.index.daemon.CatalogueIndexTaskExecutor.submitTask(CatalogueIndexTaskExecutor.java:22)
	at com.mantiki.index.daemon.CatalogueIndexTaskExecutor.submitTask(CatalogueIndexTaskExecutor.java:8)
	at com.mantiki.index.daemon.CatalogueIndexTaskCreator.createTasks(CatalogueIndexTaskCreator.java:40)
	at com.mantiki.daemon.TaskCreator.executeTasks(TaskCreator.java:40)
	at com.mantiki.daemon.MantikiDaemon.trigger(MantikiDaemon.java:201)
	at com.mantiki.index.daemon.CatalogueIndexDaemonPollingRunner.start(CatalogueIndexDaemonPollingRunner.java:26)
	at com.mantiki.daemon.MantikiDaemon.run(MantikiDaemon.java:148)
	at java.lang.Thread.run(Thread.java:745)