Apex domains cannot have CNAME records.
Question and response
Question
dig cipherviber.com. NS
Answer
cipherviber.com. 2 NS ns1.cipherviber.com.
cipherviber.com. 2 NS ns2.cipherviber.com.
Authority
The response has no authority records.
Additional
ns1.cipherviber.com. 2 A 51.161.71.71
ns2.cipherviber.com. 2 A 89.39.149.195
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0