Error establishing a database connection MYSQL:8

Compose File Below. What i am doing wrong here? version: '3.8' services: wordpress: image: wordpress:latest container_name: wp_preview environment: WORDPRESS_DB_HOST: db:3306 WORDPRESS_DB_NAME: previewdb WORDPRESS_DB_USER: previewuser WORDPRESS_DB_PASSWORD: pr3viewP4ss volumes: - ./wordpress:/var/www/html restart: always networks: - internal-network db: image: mysql:8.0 container_name: wp_db environment: MYSQL_DATABASE: previewdb MYSQL_USER: previewuser MYSQL_PASSWORD: pr3viewP4ss MYSQL_ROOT_PASSWORD: rootPass@009 volumes: - db_data:/var/lib/mysql restart: always networks: - internal-network networks: internal-network: driver: bridge
volumes: db_data: