Apex domains cannot have CNAME records.
Question and response
Question
dig blackwallnutjigs.com. NS
Answer
blackwallnutjigs.com. 5 NS ns-970.awsdns-57.net.
blackwallnutjigs.com. 5 NS ns-1786.awsdns-31.co.uk.
blackwallnutjigs.com. 5 NS ns-1795.awsdns-32.co.uk.
blackwallnutjigs.com. 5 NS ns-1854.awsdns-39.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0