Apex domains cannot have CNAME records.
Question and response
Question
dig iforexteam.com. NS
Answer
iforexteam.com. 5 NS pdns73.ultradns.org.
iforexteam.com. 5 NS pdns73.ultradns.biz.
iforexteam.com. 5 NS pdns73.ultradns.com.
iforexteam.com. 5 NS pdns73.ultradns.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0