Anvil app server - MS Azure and Ubuntu 20.04

I’ve been following the instructions on letsencrypt.

They recommend using the Certbot ACME client.

I followed the Certbot instructions on their site. When Certbot tries to issue me a certificate with:

sudo certbot certonly --standalone

I get the following error:

(env) me@azure_vm:~$ sudo certbot certonly --standalone
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator standalone, Installer None
Please enter in your domain name(s) (comma and/or space separated)  (Enter 'c'
to cancel): my_domain.org
Requesting a certificate for my_domain.org
Performing the following challenges:
http-01 challenge for my_domain.org
Waiting for verification...
Challenge failed for domain my_domain.org
http-01 challenge for my_domain.org
Cleaning up challenges
Some challenges have failed.

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

   Domain: my_domain.org
   Type:   connection
   Detail: Fetching
   http://my_domain.org/.well-known/acme-challenge/...:
   Timeout during connect (likely firewall problem)

   To fix these errors, please make sure that your domain name was
   entered correctly and the DNS A/AAAA 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.

I just purchased the domain name yesterday afternoon so perhaps I just need time. I am certainly trying to figure this out but if anything else comes to mind please let me know if you have a second.