mx02.infomaniak.com has no CNAME records.
Question and response
Question
dig mx02.infomaniak.com. NS
Answer
The response has no answer records.
Authority
infomaniak.com. 60 SOA ns1.infomaniak.ch. hostmaster.infomaniak.ch. 2026022426 900 900 604800 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0