Apex domains cannot have CNAME records.
Question and response
Question
dig etherportals.com. NS
Answer
etherportals.com. 5 NS ns1.etherportals.com.
etherportals.com. 5 NS ns2.etherportals.com.
Authority
The response has no authority records.
Additional
ns1.etherportals.com. 5 A 78.135.109.36
ns2.etherportals.com. 5 A 173.236.42.22
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0