mail03.ch.umantis.com has no MX records.
Question and response
Question
dig mail03.ch.umantis.com. MX
Answer
The response has no answer records.
Authority
umantis.com. 3600 SOA ns1.umantis.com. hostmaster.umantis.com. 2026021703 7200 1800 1209600 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0