Apex domains cannot have CNAME records.
Question and response
Question
dig arteria-net.com. NS
Answer
arteria-net.com. 4 NS ns-405.awsdns-50.com.
arteria-net.com. 4 NS ns-806.awsdns-36.net.
arteria-net.com. 4 NS ns-1204.awsdns-22.org.
arteria-net.com. 4 NS ns-1862.awsdns-40.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0