Communication Between Lightsail Containers

I want to deploy two containers which is "nginx" and "php-fpm(Laravel)".

I already create and make it work on local using docker-compose. But by Lightsail it failed. Lightsail logs said php-fpm container not found which I set the name on container.yml.

nginx: [emerg] host not found in upstream "php" in /etc/nginx/conf.d/default.conf:24

The line 24 isfastcgi_pass php:9000;, indicating the name of php container not found. Like docker-compose, I thought it would be possible with specifying container name can communicate between each containers.

So, my question is what is the right way to configure for communicate between two container.

Here is the settings.

nginx default.conf

server {
  listen 80 default_server;
  listen [::]:80 default_server;

  server_name _;

  root /app/public;

  add_header X-Frame-Options "SAMEORIGIN";
  add_header X-XSS-Protection "1; mode=block";
  add_header X-Content-Type-Options "nosniff";

  index index.html index.htm index.php;

  charset utf-8;

  location / {
      try_files $uri $uri/ /index.php?$args;
  }

  location ~ \.php$ {
    try_files $uri =404;
    fastcgi_split_path_info ^(.+\.php)(/.+)$;
    fastcgi_pass php:9000;
    fastcgi_index index.php;
    fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    fastcgi_param PATH_INFO $fastcgi_path_info;
    include fastcgi_params;
    fastcgi_buffer_size 32k;
    fastcgi_buffers 4 32k;
    fastcgi_read_timeout 1200s;
    fastcgi_send_timeout 1200s;
  }
}

Lightsail container.yml

serviceName: ${SERVICE_NAME}
containers:
    nginx:
        command: []
        image: ${LATEST_NGINX_LIGHTSAIL_DOCKER_IMAGE}
        ports:
            '80': HTTP
    php:
        command: []
        image: ${LATEST_PHP_LIGHTSAIL_DOCKER_IMAGE}
publicEndpoint:
    containerName: nginx
    containerPort: 80
    healthCheck:
        healthyThreshold: 2
        intervalSeconds: 20
        path: /api/healthcheck
        successCodes: 200-499
        timeoutSeconds: 4
        unhealthyThreshold: 2