mx.gsi-network.io has no CNAME records.
Question and response
Question
dig mx.gsi-network.io. NS
Answer
The response has no answer records.
Authority
gsi-network.io. 32 SOA dns111.ovh.net. tech.ovh.net. 2026030100 86400 3600 3600000 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0