spf2.lnmailer.net has no MX records.
Question and response
Question
dig spf2.lnmailer.net. MX
Answer
The response has no answer records.
Authority
lnmailer.net. 3600 SOA ns1.viidakko.fi. admin.dnsimple.com. 1727957525 86400 7200 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0