Apex domains cannot have CNAME records.
Question and response
Question
dig a-msedge.net. NS
Answer
a-msedge.net. 5 NS ns3.a-msedge.net.
a-msedge.net. 5 NS ns2.a-msedge.net.
a-msedge.net. 5 NS ns1.a-msedge.net.
Authority
The response has no authority records.
Additional
ns1.a-msedge.net. 5 A 204.79.197.1
ns2.a-msedge.net. 5 A 131.253.21.1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0