c1.relay.thehost.ua has no MX records.
Question and response
Question
dig c1.relay.thehost.ua. MX
Answer
The response has no answer records.
Authority
relay.thehost.ua. 3600 SOA ns1.thehost.ua. hostmaster.thehost.ua. 2021032824 10800 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0