spf.alpha-prm.jp has no MX records.
Question and response
Question
dig spf.alpha-prm.jp. MX
Answer
The response has no answer records.
Authority
alpha-prm.jp. 1800 SOA fjkdns99.alpha-prm.jp. hostmaster.alpha-prm.jp. 2026021001 10800 3600 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0