mailserver.web-project.uk has no CNAME records.
Question and response
Question
dig mailserver.web-project.uk. NS
Answer
The response has no answer records.
Authority
web-project.uk. 1593 SOA clark.ns.cloudflare.com. dns.cloudflare.com. 2397362308 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0