curl: (7) Failed connect to packages.gitlab.com:443; Connection refused

Hi all, I wish to install gitlab at my centos7 by follow the tutorial here https://about.gitlab.com/install/#centos-7

but the error shows me

[root@enlabsapp067 deployer]# curl https://packages.gitlab.com/install/repositories/gitlab/gitlab-ee/script.rpm.sh | sudo bash % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 0 0 0 0 0 0 0 0 --:--:-- 0:00:05 --:--:-- 0curl: (7) Failed connect to packages.gitlab.com:443; Connection refused

Your kind assist is much appreciated.