ns3.stableserver.net has no CNAME records.
Question and response
Question
dig ns3.stableserver.net. NS
Answer
The response has no answer records.
Authority
stableserver.net. 2298 SOA ns1.stableserver.net. postmaster.stableserver.net. 2026022409 3600 3600 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0