ns.sunic.ua has no MX records.
Question and response
Question
dig ns.sunic.ua. MX
Answer
The response has no answer records.
Authority
sunic.ua. 300 SOA ns.sunic.ua. hostmaster.ns.sunic.ua. 2026011501 300 7200 604800 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0