Doesn't seem to be possible to install OpenVPN client

I tried

rpm-ostree install openvpn3-client

rpm-ostree install openvpn3-client

rpm-ostree install openvpn3-client

rpm-ostree install openvpn3-client . Which did not seem to work:

error: Packages not found: openvpn3-client

error: Packages not found: openvpn3-client

error: Packages not found: openvpn3-client

error: Packages not found: openvpn3-client

Anyone know how to install?