Apex domains cannot have CNAME records.
Question and response
Question
dig cascadecloud.co.uk. NS
Answer
cascadecloud.co.uk. 4 NS ns-1096.awsdns-09.org.
cascadecloud.co.uk. 4 NS ns-786.awsdns-34.net.
cascadecloud.co.uk. 4 NS ns-329.awsdns-41.com.
cascadecloud.co.uk. 4 NS ns-1656.awsdns-15.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0