smtp.el-dokument.net has no MX records.
Question and response
Question
dig smtp.el-dokument.net. MX
Answer
The response has no answer records.
Authority
el-dokument.net. 3600 SOA ns1.superhosting.cz. dns.superhosting.cz. 2026030401 3600 3600 2592000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0