Lavarel project with nginx server return 404|Not Found but works fine with default /var/www/html root

I am using Digital Ocean VPS with a LEMP stack. I am struggling in the problem that return 404|not Found when accessing to my website. My lavarel project is stored as /var/www/html/api. It works fine with default /var/www/html root. My current config file is:

server {
    listen 80 default_server;
    listen [::]:80 default_server;
    root /var/www/html/api/public;
    #root /var/www/html; //ok

    # Add index.php to the list if you are using PHP
    index index.php index.html index.htm index.nginx-debian.html;

    server_name ipaddress;
    client_max_body_size 64M;
    location / {

            try_files $uri $uri/ /index.php$is_args$args;
    }
    location ~ \.php$ {

            include snippets/fastcgi-php.conf;
            fastcgi_pass unix:/run/php/php7.2-fpm.sock;
    }
}

Any help would be appreciative. Thanks a lot.