letsencrypt certbot timeout error

I am getting this weird letsencrypt error while trying to run the command

$ certbot certonly --standalone --email example@gmail.com --agree-tos -n -d trumporate.com,www.trumporate.com
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Obtaining a new certificate
Performing the following challenges:
tls-sni-01 challenge for trumporate.com
tls-sni-01 challenge for www.trumporate.com
Waiting for verification...
Cleaning up challenges
Failed authorization procedure. trumporate.com (tls-sni-01): urn:acme:error:connection :: The server could not connect to the client to verify the domain :: Timeout, www.trumporate.com (tls-sni-01): urn:acme:error:connection :: The server could not connect to the client to verify the domain :: Timeout

IMPORTANT NOTES:
 - The following errors were reported by the server:

   Domain: trumporate.com
   Type:   connection
   Detail: Timeout

   Domain: www.trumporate.com
   Type:   connection
   Detail: Timeout

   To fix these errors, please make sure that your domain name was
   entered correctly and the DNS A record(s) for that domain
   contain(s) the right IP address. Additionally, please check that
   your computer has a publicly routable IP address and that no
   firewalls are preventing the server from communicating with the
   client. If you're using the webroot plugin, you should also verify
   that you are serving files from the webroot path you provided.

Right now I have generated the file dhparam using

$ sudo openssl dhparam -out /etc/ssl/certs/dhparam.pem 2048

Here is my current nginx conf file

$ cat /etc/nginx/sites-available/trumporate 
server {
    listen 80;
    server_name trumporate.com www.trumporate.com; 

    location / {
        include proxy_params;
        proxy_redirect off;
        proxy_pass http://127.0.0.1:5000;
    }
}

Not sure where am I going wrong. Should trumporate.com be resolvable on this vm where I am running certbot?

stopped nginx and ran it again, gave the same error

I have registered the domain through route53. It's got 2 type A records pointing to the elastic IP attached to the ec2 box. one for the www version and one without it and has 4 NS records and an SOA record which I think were there by default when creating the hosting zone