mx1.gabia.com has no CNAME records.
Question and response
Question
dig mx1.gabia.com. NS
Answer
The response has no answer records.
Authority
gabia.com. 205 SOA ns.gabia.co.kr. hosting.gabia.com. 2023031322 1800 60 1209600 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0