The server is not registered with a known Red Hat base channel

hi i so need help for this problem i buy cpanel from amazone aws and in my install whm i have this error message [root@ip-172-31-43-4 ~]# sh latest Verifying archive integrity... All good. Uncompressing cPanel & WHM Installer...... ____ _ ___| _ \ __ _ _ __ ___| | / __| |_) / _` | '_ \ / _ \ | | (__| __/ (_| | | | | __/ | \___|_| \__,_|_| |_|\___|_| Installer Version v00071 r567a617660c2d5c38ae1649f5ede2067aee6ee7e Beginning main installation. 2018-02-07 08:04:44 777 ( INFO): cPanel & WHM installation started at: Wed Feb 7 08:04:44 2018! 2018-02-07 08:04:44 778 ( INFO): This installation will require 20-50 minutes, depending on your hardware. 2018-02-07 08:04:44 779 ( INFO): Now is the time to go get another cup of coffe e/jolt. 2018-02-07 08:04:44 780 ( INFO): The install will log to the /var/log/cpanel-in stall.log file. 2018-02-07 08:04:44 781 ( INFO): 2018-02-07 08:04:44 782 ( INFO): Beginning Installation v3... 2018-02-07 08:04:44 456 ( INFO): redhat-server 7.4 (Linux) detected! 2018-02-07 08:04:44 472 ( INFO): Checking RAM now... 2018-02-07 08:04:44 532 ( INFO): Validating that the system hostname ('vps.sort x.net') is a FQDN... 2018-02-07 08:04:44 556 ( INFO): Checking for NetworkManager now... 2018-02-07 08:04:44 598 ( WARN): NetworkManager is installed, but not active. Consider removing it. ..... 2018-02-07 08:04:49 568 ( INFO): Checking for essential system files... 2018-02-07 08:04:49 1232 ( INFO): Checking the Red Hat registration for updates. .. 2018-02-07 08:04:51 1283 ( INFO): Validating that the system subscribed to the o ptional RHN channel... 2018-02-07 08:04:51 1303 (ERROR): The server is not registered with a known Red Hat base channel. 2018-02-07 08:04:51 1304 (ERROR): $> /usr/bin/yum repolist enabled 2018-02-07 08:04:51 1305 (ERROR): Loaded plugins: amazon-id, rhui-lb, search-dis abled-repos repo id repo name status rhui-REGION-client-config-server-7/x86_64 Red Hat Update Infrastru 2 rhui-REGION-rhel-server-releases/7Server/x86_64 Red Hat Enterprise Linux 18035 rhui-REGION-rhel-server-rh-common/7Server/x86_64 Red Hat Enterprise Linux 231 repolist: 18268 Removing /root/installer.lock. [root@ip-172-31-43-4 ~]# subscription-manager repos --enable rhel-6-server-opti