Apex domains cannot have CNAME records.
Question and response
Question
dig elpos.net. NS
Answer
elpos.net. 5 NS dns.elpos.net.
elpos.net. 5 NS dns2.elpos.net.
Authority
The response has no authority records.
Additional
dns.elpos.net. 5 A 85.193.224.6
dns2.elpos.net. 5 A 85.193.224.2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0