I just recently upgraded a Magento project from 2.2.5 to 2.3.4, went in the Catalog Search configuration to change to use Elastic Search 6, tested connection successfully. However when trying to run reindex
bin/magento indexer:reindex catalogsearch_fulltext
I got this error:
Undefined index: elasticsearch6 in /app/vendor/magento/module-elasticsearch/Elasticsearch5/Model/Adapter/FieldMapper/ProductFieldMapperProxy.php on line 44
Does anyone know how to resolve this? Why is it trying to call from Elasticsearch5 module?