Apex domains cannot have CNAME records.
Question and response
Question
dig greatscotshop.com. NS
Answer
greatscotshop.com. 1 NS ns-905.awsdns-49.net.
greatscotshop.com. 1 NS ns-1291.awsdns-33.org.
greatscotshop.com. 1 NS ns-1901.awsdns-45.co.uk.
greatscotshop.com. 1 NS ns-542.awsdns-03.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0