Apex domains cannot have CNAME records.
Question and response
Question
dig thornremover.com. NS
Answer
thornremover.com. 5 NS ns-1383.awsdns-44.org.
thornremover.com. 5 NS ns-1083.awsdns-07.org.
thornremover.com. 5 NS ns-1275.awsdns-31.org.
thornremover.com. 5 NS ns-1649.awsdns-14.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0