sub234-10.elpos.net has no MX records.
Question and response
Question
dig sub234-10.elpos.net. MX
Answer
The response has no answer records.
Authority
elpos.net. 1800 SOA dns.elpos.net. administrator.elpos.net. 2026030401 1800 3600 1209600 1800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0