iristel.ch has no MX records.
Question and response
Question
dig iristel.ch. MX
Answer
The response has no answer records.
Authority
iristel.ch. 86400 SOA pdns104.ultradns.com. tldadmin.iristel.com. 2021020814 86400 86400 86400 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0