Apex domains cannot have CNAME records.
Question and response
Question
dig hpe.com. NS
Answer
hpe.com. 3 NS ns5.hpe.com.
hpe.com. 3 NS ns8.hpe.com.
hpe.com. 3 NS ns3.hpe.com.
hpe.com. 3 NS ns6.hpe.com.
hpe.com. 3 NS ns1.hpe.com.
hpe.com. 3 NS ns4.hpe.com.
hpe.com. 3 NS ns7.hpe.com.
hpe.com. 3 NS ns2.hpe.com.
Authority
The response has no authority records.
Additional
ns1.hpe.com. 3 A 192.58.206.184
ns2.hpe.com. 3 A 192.58.207.221
ns3.hpe.com. 3 A 16.2.141.20
ns4.hpe.com. 3 A 16.2.138.125
ns5.hpe.com. 3 A 192.58.206.184
ns6.hpe.com. 3 A 192.58.207.221
ns7.hpe.com. 3 A 16.2.141.21
ns8.hpe.com. 3 A 16.2.138.125
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0