Apex domains cannot have CNAME records.
Question and response
Question
dig zhub.com. NS
Answer
zhub.com. 2 NS ns2.zhub.com.
zhub.com. 2 NS ns1.zhub.com.
Authority
The response has no authority records.
Additional
ns1.zhub.com. 2 A 148.72.155.208
ns2.zhub.com. 2 A 207.38.87.15
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0