Apex domains cannot have CNAME records.
Question and response
Question
dig vodafone.ro. NS
Answer
vodafone.ro. 5 NS ns1.vtv-prod.vodafone.ro.
vodafone.ro. 5 NS ns02.vodafonenet.ro.
vodafone.ro. 5 NS ns01.vodafonenet.ro.
Authority
The response has no authority records.
Additional
ns01.vodafonenet.ro. 5 A 213.233.64.250
ns02.vodafonenet.ro. 5 A 46.97.92.8
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0