Apex domains cannot have CNAME records.
Question and response
Question
dig vispa.net.uk. NS
Answer
vispa.net.uk. 1 NS ns6.vispa.uk.net.
vispa.net.uk. 1 NS ns0.vispa.net.uk.
vispa.net.uk. 1 NS ns1.vispa.net.uk.
vispa.net.uk. 1 NS ns7.vispa.uk.net.
Authority
The response has no authority records.
Additional
ns0.vispa.net.uk. 1 A 217.28.16.9
ns1.vispa.net.uk. 1 A 217.28.16.10
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0