poczta.m3.net.pl has no MX records.
Question and response
Question
dig poczta.m3.net.pl. MX
Answer
The response has no answer records.
Authority
m3.net.pl. 3600 SOA ns1.tld.pl. admin.tld.pl. 2026020502 10800 1800 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0