ATF is currently blocked in France. Unclear, if the block is done on a DNS-level or what. Using a different DNS resolver from your ISP, a VPN or Tor should resolve the issue.
Past Incidents
Sunday 29th March 2020
Routing issue
There seems to have been a routing issue and the site was unreachable from some places, Finland at least was affected. Not sure when it exactly began but it lasted an hour or more.