mail22.easybill.io has no CNAME records.
Question and response
Question
dig mail22.easybill.io. NS
Answer
The response has no answer records.
Authority
easybill.io. 1439 SOA hydrogen.ns.hetzner.com. dns.hetzner.com. 2026030601 86400 10800 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0