Apex domains cannot have CNAME records.
Question and response
Question
dig domainnetwork.com. NS
Answer
domainnetwork.com. 4 NS udns1.cscudns.com.
domainnetwork.com. 4 NS udns2.cscudns.org.
Authority
The response has no authority records.
Additional
udns1.cscudns.com. 1 A 204.74.66.14
udns2.cscudns.org. 1 A 204.74.104.20
udns1.cscudns.com. 1 AAAA 2001:502:4612:0:0:0:0:20e
udns2.cscudns.org. 1 AAAA 2610:a1:3214:0:0:0:0:53
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0