Apex domains cannot have CNAME records.
Question and response
Question
dig eolo.it. NS
Answer
eolo.it. 5 NS ns1-cf.eolo.it.
eolo.it. 5 NS ns4-cf.eolo.it.
eolo.it. 5 NS ns5-cf.eolo.it.
eolo.it. 5 NS ns2-cf.eolo.it.
eolo.it. 5 NS ns3-cf.eolo.it.
Authority
The response has no authority records.
Additional
ns1-cf.eolo.it. 5 A 162.159.10.110
ns2-cf.eolo.it. 5 A 162.159.9.231
ns3-cf.eolo.it. 5 A 198.41.222.103
ns4-cf.eolo.it. 5 A 173.245.59.34
ns5-cf.eolo.it. 5 A 173.245.58.7
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0