Please check our status page to make sure there are no issues with our servers.
If you have a strict firewall then please ensure that the port 6789 is opened for TCP.
The issue could be also be due to some filtering on your network and/or ISP. Please contact your ISP and let them know that you are having connectivity issues to the following hostname: achi.faceit.com
If none of these solutions work for you, we would kindly ask you to get in touch with us via this link and our dedicated CS team will assist in getting you up and running: Contact Support