Hi Bao,
Please navigate to the web config file of the Orchestrator. It will be located in the server where Orchestrator is configured.
Open the web config
search for ElasticSearch - Note that there will be 2 elasticsearch (RobotElasticSearch and ServerElasticSearch). Under this tag, there will be Uri=“xxxxxx”. Please make it empty under RobotElasticSearch. Restart the IIS of the Orchestrator. allow 2 mins time since there will be some delay. Then you can see the logs populating.