Apex domains cannot have CNAME records.
Question and response
Question
dig billgilmourcpa.com. NS
Answer
billgilmourcpa.com. 5 NS ns-1812.awsdns-34.co.uk.
billgilmourcpa.com. 5 NS ns-1786.awsdns-31.co.uk.
billgilmourcpa.com. 5 NS ns-279.awsdns-34.com.
billgilmourcpa.com. 5 NS ns-291.awsdns-36.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0