Apex domains cannot have CNAME records.
Question and response
Question
dig messagesystems.com. NS
Answer
messagesystems.com. 5 NS ns-197.awsdns-24.com.
messagesystems.com. 5 NS ns-1755.awsdns-27.co.uk.
messagesystems.com. 5 NS ns-1026.awsdns-00.org.
messagesystems.com. 5 NS ns-579.awsdns-08.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0