I have this nginx server configured which works fine when acessed over internal network i.e. where my nginx server is located, but when I try to access it over external network using same server_name using rassd.media(my DNS) it loads frontend but unable to access any backend APIs.

my nginx.conf

user www-data;
worker_processes auto;

error_log /var/log/nginx/error.log;
pid /var/run/nginx.pid;

events {
    worker_connections 1024;
}

http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;

    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for"';

    access_log /var/log/nginx/access.log main;

    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;

    # Server block for serving React frontend on port 3000
    server {
#        listen 3000;
#        server_name _;

        listen 3000;
        server_name abcc www.abcc;

        root /home/fe/build;
        index index.html;

        location / {
            try_files $uri /index.html;
        }
    }

    # New server block for rassd.media
    server {
        listen 80;
        server_name rassd.media;

        # Global CORS header for this server block
        #more_set_headers 'Access-Control-Allow-Origin: *';
        add_header 'Access-Control-Allow-Origin' '*' always;
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS, PUT, PATCH, DELETE' always;
        add_header 'Access-Control-Allow-Headers' 'DNT, User-Agent, X-Requested-With, If-Modified-Since, Cache-Control, Content-Type, Range' always;
        add_header 'Access-Control-Expose-Headers' 'Content-Length, Content-Range' always;

        root /home/fe/build;  # Serve the same React frontend directory
        index index.html;

        location / {
            try_files $uri /index.html;  # Handle SPA routing
        }
    }


    server {
        listen 80 default_server;
        server_name rassd.media _;
        root /;


        client_body_timeout 60s;  # Adjust the timeout as needed
        client_header_timeout 60s;

        location /search-engine/ {
            rewrite ^/search-engine/(.*)$ /$1 break;
            proxy_pass http://172.30.30.66:8084/;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;
        }

        location /user-service/ {
            rewrite ^/user-service/(.*)$ /$1 break;
            proxy_pass http://172.30.30.56:8191/;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;
        }


    }
}

I tried combining both block in and keeping root of root "/home/fe/build;" but everything stopped working from it I know root of BE and FE are different, is there something I am missing.

P.S. I am not well versed in these nginx configurations so it might be a rookie mistake so any guidance is appreciated. Thanks