Apex domains cannot have CNAME records.
Question and response
Question
dig nexxohub.com. NS
Answer
nexxohub.com. 4 NS ns-1603.awsdns-08.co.uk.
nexxohub.com. 4 NS ns-1758.awsdns-27.co.uk.
nexxohub.com. 4 NS ns-96.awsdns-12.com.
nexxohub.com. 4 NS ns-1728.awsdns-24.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0