Apex domains cannot have CNAME records.
Question and response
Question
dig ets.net. NS
Answer
ets.net. 3 NS ns-1793.awsdns-32.co.uk.
ets.net. 3 NS ns-504.awsdns-63.com.
ets.net. 3 NS ns-672.awsdns-20.net.
ets.net. 3 NS ns-1202.awsdns-22.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0