smtp.bg.pwr.edu.pl has no MX records.
Question and response
Question
dig smtp.bg.pwr.edu.pl. MX
Answer
The response has no answer records.
Authority
pwr.edu.pl. 7200 SOA dns1.pwr.edu.pl. dns.pwr.edu.pl. 2026030401 3600 300 1209600 7200
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0