mailgate.ukrtelecom.net has no CNAME records.
Question and response
Question
dig mailgate.ukrtelecom.net. NS
Answer
The response has no answer records.
Authority
ukrtelecom.net. 3600 SOA ns1-03.azure-dns.com. hostmaster.ukrtel.net. 2021092900 10800 3600 3600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0