Apex domains cannot have CNAME records.
Question and response
Question
dig listaurant.com. NS
Answer
listaurant.com. 5 NS ns-1797.awsdns-32.co.uk.
listaurant.com. 5 NS ns-1558.awsdns-02.co.uk.
listaurant.com. 5 NS ns-1978.awsdns-55.co.uk.
listaurant.com. 5 NS ns-1892.awsdns-44.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0