symfony raw sql from table based on 2 server

I have 2 database server so I defined my doctrine in following way:

doctrine:dbal:default_connection: defaultconnections:default:# configure these for your database serverdriver: 'pdo_mysql'server_version: 'mariadb-10.3.16'charset: utf8default_table_options:charset: utf8collate: utf8_unicode_ci

            url: '%env(resolve:DATABASE_URL)%'        customer:            driver: 'pdo_mysql'            server_version: 'mariadb-10.3.16'            charset: utf8            default_table_options:                charset: utf8                collate: utf8_unicode_ci            url: '%env(resolve:DATABASE_CUSTOMER_URL)%'orm:    auto_generate_proxy_classes: true    naming_strategy: doctrine.orm.naming_strategy.underscore_number_aware    auto_mapping: true    mappings:        App:            is_bundle: false            type: annotation            dir: '%kernel.project_dir%/src/Entity'            prefix: 'App\Entity'            alias: App

Now I need to make the query from table inside customer server:

$qb = $this->connection->createQueryBuilder()           ->select(*)           ->from('customer.tbl_user')

I am not being able to run this query. Can anybody help me how can I setup this multiple database connection ?