mail13.easybill.io has no MX records.
Question and response
Question
dig mail13.easybill.io. MX
Answer
The response has no answer records.
Authority
easybill.io. 3600 SOA hydrogen.ns.hetzner.com. dns.hetzner.com. 2026030500 86400 10800 3600000 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0