postak.nwt.cz has no MX records.
Question and response
Question
dig postak.nwt.cz. MX
Answer
The response has no answer records.
Authority
nwt.cz. 3600 SOA ns.nwt.cz. jv.nwt.cz. 2026022301 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0