Apex domains cannot have CNAME records.
Question and response
Question
dig dorsetseaviewcottages.com. NS
Answer
dorsetseaviewcottages.com. 3 NS ns2.dorsetseaviewcottages.com.
dorsetseaviewcottages.com. 3 NS ns1.dorsetseaviewcottages.com.
Authority
The response has no authority records.
Additional
ns1.dorsetseaviewcottages.com. 3 A 51.68.138.200
ns2.dorsetseaviewcottages.com. 3 A 51.83.169.192
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0