unknown.hostihc.sk has no MX records.
Question and response
Question
dig unknown.hostihc.sk. MX
Answer
The response has no answer records.
Authority
hostihc.sk. 3600 SOA ns1.sk.eserver.net. hostmaster.hostihc.sk. 2023102602 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0