mx1.seofr.uk has no NS records.
NS records for this zone are defined at seofr.uk.
NS records for this zone are defined at seofr.uk.
Question and response
Question
dig mx1.seofr.uk. NS
Answer
The response has no answer records.
Authority
seofr.uk. 1800 SOA elma.ns.cloudflare.com. dns.cloudflare.com. 2397777668 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0