Unable to create gateway connection for SQL Server

Thank you for your infomation. I have tried following steps and adding entries on SqlTrustedServers field in gateway config file, but still it would not allow me to create such SQL Server on-premise gateway connection😓. 

Another thing I tried: OLE DB connection type works fine in gateway new connection creation as it provides "TrustServerCertificate=True" in connection string. However, OLE DB data souce from PBI desktop once published to the service, it becomes SQL Server connection type again and be un-able to add such parameter in the connection.