I changed my Obi's DNS to 1.1.1.1 and 1.0.0.1 and I'm back in action.
Not sure if it just flushed the cache.
If you can't find where to do this, go to the IP address of your device in a web browser (something like
http://192.168.1.54 ) and use admin/admin to login.
Go to System Management -> WAN Settings.
Uncheck DNSServer1 and DNSServer2 at Default on the right.
Enter: 1.1.1.1 in one and 1.0.0.1 in the other.
Save at the bottom.
Reboot at the top right.
That's what did the trick for me.