spf2.sbr-master.net has no MX records.
Question and response
Question
dig spf2.sbr-master.net. MX
Answer
The response has no answer records.
Authority
sbr-master.net. 3600 SOA ns1.sarbacane-dns.com. abuse.sarbacane.com. 2026021901 21600 3600 86400 172800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0