Apex domains cannot have CNAME records.
Question and response
Question
dig conns.com. NS
Answer
conns.com. 5 NS ns-827.awsdns-39.net.
conns.com. 5 NS ns-1992.awsdns-57.co.uk.
conns.com. 5 NS ns-228.awsdns-28.com.
conns.com. 5 NS ns-1094.awsdns-08.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0