Apex domains cannot have CNAME records.
Question and response
Question
dig recruitmail.com. NS
Answer
recruitmail.com. 5 NS ns-1331.awsdns-38.org.
recruitmail.com. 5 NS ns-1649.awsdns-14.co.uk.
recruitmail.com. 5 NS ns-495.awsdns-61.com.
recruitmail.com. 5 NS ns-886.awsdns-46.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0