smtp2.espo.cz has no MX records.
Question and response
Question
dig smtp2.espo.cz. MX
Answer
The response has no answer records.
Authority
espo.cz. 3600 SOA mail.espo.cz. michals.espo.cz. 2026030220 900 600 86400 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0