Node Server Killed while transferring file bigger that 60 MB

I am using a Droplet with 1GB RAM and 1vCPU configuration to upload files from nodejs server.

Whenever I try to upload file bigger than 60MB node server gets killed.

My Nginx Default file config.

                proxy_pass http://localhost:8081;
                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;
                proxy_set_header Upgrade $http_upgrade;
                proxy_set_header Connection 'upgrade';
                proxy_cache_bypass $http_upgrade;
                proxy_max_temp_file_size 0;
                proxy_connect_timeout 1800s;
                proxy_send_timeout 1800s;
                proxy_read_timeout 1800s;
                proxy_buffer_size 128k;
                proxy_buffers 128 256k;
                proxy_busy_buffers_size 256k;
                proxy_redirect off;
                proxy_request_buffering off;
                proxy_buffering off;

My nginx.conf file

        sendfile on;
        tcp_nopush on;
        tcp_nodelay on;
        keepalive_timeout 1800;
        types_hash_max_size 2048;
        client_max_body_size 4096M;
        fastcgi_read_timeout 1800s;
        client_body_timeout 1800s;
        client_header_timeout 1800s;

I am trying to solve this issue for hours and stuck.

Please help me out here!!