mail03.mailit.app has no CNAME records.
Question and response
Question
dig mail03.mailit.app. NS
Answer
The response has no answer records.
Authority
mailit.app. 10773 SOA ns1.first-ns.de. dns.hetzner.com. 2025022001 14400 1800 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0