Apex domains cannot have CNAME records.
Question and response
Question
dig telnetwork.it. NS
Answer
telnetwork.it. 5 NS ns1.telnetwork.it.
telnetwork.it. 5 NS ns0.telnetwork.it.
Authority
The response has no authority records.
Additional
ns0.telnetwork.it. 5 A 195.36.1.110
ns1.telnetwork.it. 5 A 195.36.1.100
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0