AWS: Your system is not supported by certbot-auto anymore
According to https://community.letsencrypt.org/t/certbot-1-9-0-release/135414 :
Changed
certbot-auto was deprecated on all systems except for those based on Debian or RHEL.
And from this website: https://community.letsencrypt.org/t/fail-to-detect-amazon-linux-2-certbot/136140
The best chance to get Certbot working on Amazon Linux 2 is to install the rpm from EPEL as described here: https://aws.amazon.com/blogs/compute/extending-amazon-linux-2-with-epel-and-lets-encrypt/
Here is instructions on how to install certbot on any system: https://certbot.eff.org/instructions
Particularly for Ubuntu 18.04 with Nginx webserver I was able to install certbot using the following commands:
snap install core
snap refresh core
snap install --classic certbot
Then you can run certbot using certbot
command