mx.teliacygate.fi has no CNAME records.
Question and response
Question
dig mx.teliacygate.fi. NS
Answer
The response has no answer records.
Authority
teliacygate.fi. 900 SOA ns1.cygate.fi. hostmaster.cygate.fi. 2018111740 28800 7200 604800 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0