_spf.mx.dns.md has no MX records.
Question and response
Question
dig _spf.mx.dns.md. MX
Answer
The response has no answer records.
Authority
dns.md. 3600 SOA ns.dns.md. master.dns.md. 2026021111 43200 3600 2419200 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0