mail.nsauth3.trans-ix.com has no CNAME records.
Question and response
Question
dig mail.nsauth3.trans-ix.com. NS
Answer
The response has no answer records.
Authority
nsauth3.trans-ix.com. 3600 SOA nsauth1.trans-ix.nl. root.nsauth3.trans-ix.com. 2022012702 3600 3600 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0