mx10.migadu.com has no CNAME records.
Question and response
Question
dig mx10.migadu.com. NS
Answer
The response has no answer records.
Authority
migadu.com. 2170 SOA ns0.migadu.com. hostmaster.migadu.com. 1771923152 1200 900 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0