Apex domains cannot have CNAME records.
Question and response
Question
dig seinternal.com. NS
Answer
seinternal.com. 2 NS ns-164.awsdns-20.com.
seinternal.com. 2 NS ns-1614.awsdns-09.co.uk.
seinternal.com. 2 NS ns-1171.awsdns-18.org.
seinternal.com. 2 NS ns-866.awsdns-44.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0