Apex domains cannot have CNAME records.
Question and response
Question
dig pdxdns.net. NS
Answer
pdxdns.net. 5 NS g-ns3.pdxdns.net.
pdxdns.net. 5 NS g-ns4.pdxdns.net.
pdxdns.net. 5 NS g-ns1.pdxdns.net.
pdxdns.net. 5 NS g-ns2.pdxdns.net.
Authority
The response has no authority records.
Additional
g-ns1.pdxdns.net. 5 A 185.136.96.65
g-ns2.pdxdns.net. 5 A 185.136.97.65
g-ns3.pdxdns.net. 5 A 185.136.98.65
g-ns4.pdxdns.net. 5 A 185.136.99.65
g-ns1.pdxdns.net. 5 AAAA 2a06:fb00:1:0:0:0:1:65
g-ns2.pdxdns.net. 5 AAAA 2a06:fb00:1:0:0:0:2:65
g-ns3.pdxdns.net. 5 AAAA 2a06:fb00:1:0:0:0:3:65
g-ns4.pdxdns.net. 5 AAAA 2a06:fb00:1:0:0:0:4:65
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0