Currently we are seeing a DDOS against our DNS resolvers, as many servers are using these you may be having issues as well.

While we are currently focusing on solving these issues a solution to get it solved instantly would be to set any of the resolvers from one of the following:

Google 8.8.8.8,8.8.4.4
OpenDNS 208.67.222.222,208.67.220.220
Cloudflare 1.1.1.1

Update 15:35:
Currently DDOS is mitigated, we will keep monitoring the situation.