Apex domains cannot have CNAME records.
Question and response
Question
dig arthurmcsh.com. NS
Answer
arthurmcsh.com. 5 NS ns-1533.awsdns-63.org.
arthurmcsh.com. 5 NS ns-526.awsdns-01.net.
arthurmcsh.com. 5 NS ns-865.awsdns-44.net.
arthurmcsh.com. 5 NS ns-1137.awsdns-14.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0