Apex domains cannot have CNAME records.
Question and response
Question
dig hope-mail.com. NS
Answer
hope-mail.com. 5 NS ns-1399.awsdns-46.org.
hope-mail.com. 5 NS ns-1674.awsdns-17.co.uk.
hope-mail.com. 5 NS ns-421.awsdns-52.com.
hope-mail.com. 5 NS ns-558.awsdns-05.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0