Apex domains cannot have CNAME records.
Question and response
Question
dig fornex.com. NS
Answer
fornex.com. 5 NS dns4.fornex.com.
fornex.com. 5 NS dns1.fornex.com.
fornex.com. 5 NS dns2.fornex.com.
fornex.com. 5 NS dns3.fornex.com.
Authority
The response has no authority records.
Additional
dns1.fornex.com. 5 A 162.159.8.250
dns2.fornex.com. 5 A 162.159.9.76
dns3.fornex.com. 5 A 162.159.10.190
dns4.fornex.com. 5 A 162.159.11.188
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0