Apex domains cannot have CNAME records.
Question and response
Question
dig mtaroutes.com. NS
Answer
mtaroutes.com. 5 NS ns-1584.awsdns-06.co.uk.
mtaroutes.com. 5 NS ns-1272.awsdns-31.org.
mtaroutes.com. 5 NS ns-61.awsdns-07.com.
mtaroutes.com. 5 NS ns-838.awsdns-40.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0