spf.hosts.co.uk has no MX records.
Question and response
Question
dig spf.hosts.co.uk. MX
Answer
The response has no answer records.
Authority
hosts.co.uk. 86400 SOA ns0.phase8.net. support.phase8.net. 2025022701 28800 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0