My client is using Azure DNS nameservers for their DNS records/SOA. We noticed this morning that they were receiving no mail and their website returned a "server DNS address could not be found" error.
NSLOOKUP yields a "Non-existent" domain for any record lookup. The records themselves are still present in the portal.azure.com "DNS Zones" section.
Specifying Azure's nameservers resolves the records fine; literally every other nameserver yields the "non-existent" error.
What can this be?
