I cannot get certbot to install on a particular AWS EC2 Linux instance

I’m trying to install certbot on the instance where we have a Bitnami Trac/SVN stack and a Tomcat server installed, and when I do yum install -y certbot python2-certbot-apache I keep getting No package certbot available. No package python2-certbot-apache available. Error: Nothing to do But it worked fine on another (newer) instance, the one hosting…