Apex domains cannot have CNAME records.
Question and response
Question
dig heavencell.com. NS
Answer
heavencell.com. 5 NS ns-2045.awsdns-63.co.uk.
heavencell.com. 5 NS ns-563.awsdns-06.net.
heavencell.com. 5 NS ns-119.awsdns-14.com.
heavencell.com. 5 NS ns-1464.awsdns-55.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0