dns.acimmonaco.com has no CNAME records.
Question and response
Question
dig dns.acimmonaco.com. NS
Answer
The response has no answer records.
Authority
acimmonaco.com. 1453 SOA dns.acimmonaco.com. hostmaster.acimmonaco.com. 1724540953 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0