Apex domains cannot have CNAME records.
Question and response
Question
dig acanow.com. NS
Answer
acanow.com. 5 NS ns-837.awsdns-40.net.
acanow.com. 5 NS ns-1630.awsdns-11.co.uk.
acanow.com. 5 NS ns-1478.awsdns-56.org.
acanow.com. 5 NS ns-1152.awsdns-16.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0