Apex domains cannot have CNAME records.
Question and response
Question
dig mir3.com. NS
Answer
mir3.com. 5 NS ns-880.awsdns-46.net.
mir3.com. 5 NS ns-1610.awsdns-09.co.uk.
mir3.com. 5 NS ns-319.awsdns-39.com.
mir3.com. 5 NS ns-1474.awsdns-56.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0