spf1.a1.hr has no MX records.
Question and response
Question
dig spf1.a1.hr. MX
Answer
The response has no answer records.
Authority
a1.hr. 86400 SOA dnsa.a1.hr. dnsadmin.a1.hr. 2026021301 14400 3600 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0