_spf-shared.si-shell.net has no MX records.
Question and response
Question
dig _spf-shared.si-shell.net. MX
Answer
The response has no answer records.
Authority
si-shell.net. 3600 SOA ns1.freedns.si. info.si-shell.net. 2026031006 600 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0