_spf.smaily.com has no MX records.
Question and response
Question
dig _spf.smaily.com. MX
Answer
The response has no answer records.
Authority
smaily.com. 3600 SOA ns.elkdata.ee. hostmaster.ns.elkdata.ee. 2025093000 10800 1800 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0