You have to maintain an active subscription in order to be able to use the repository!
The EPEL repository usually contains quite a recent, but not always the latest version of Ansible.
To get absolutely latest, yet stable version of Ansible, add this official repository.
[ansible] name=Ansible RPM repository for Enterprise Linux 7 - $basearch baseurl=https://releases.ansible.com/ansible/rpm/release/epel-7-$basearch/ enabled=1 gpgcheck=1 gpgkey=https://releases.ansible.com/keys/RPM-GPG-KEY-ansible-release.pub
Alternatively, you can do:
yum install https://extras.getpagespeed.com/release-el7-latest.rpm yum install ansible-release