Apex domains cannot have CNAME records.
Question and response
Question
dig analystbootcamplondon.com. NS
Answer
analystbootcamplondon.com. 5 NS ns2.analystbootcamplondon.com.
analystbootcamplondon.com. 5 NS ns1.analystbootcamplondon.com.
Authority
The response has no authority records.
Additional
ns1.analystbootcamplondon.com. 5 A 142.44.136.25
ns2.analystbootcamplondon.com. 5 A 51.222.0.6
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0