This happens because port 80 has been reserved for a running process. Which means there could be a web server running behind, i.e. Apache, Nginx, etc. You will need to turn off the webserver or software that using port 80 first and rerun the command to let it spin up a certbot HTTP server for verification.
Here is the example of commands to solve the issue:
systemctl stop nginx
certbot renew
systemctl start nginx Reference:
EFF certbot – https://certbot.eff.org/
