Apex domains cannot have CNAME records.
Question and response
Question
dig tcecareers.com. NS
Answer
tcecareers.com. 5 NS ns-583.awsdns-08.net.
tcecareers.com. 5 NS ns-501.awsdns-62.com.
tcecareers.com. 5 NS ns-402.awsdns-50.com.
tcecareers.com. 5 NS ns-1005.awsdns-61.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0