Apex domains cannot have CNAME records.
Question and response
Question
dig virtualxs.com. NS
Answer
virtualxs.com. 5 NS ns4.virtualxs.com.
virtualxs.com. 5 NS ns6.virtualxs.com.
virtualxs.com. 5 NS ns2.virtualxs.com.
virtualxs.com. 5 NS ns8.virtualxs.com.
virtualxs.com. 5 NS ns1.virtualxs.com.
virtualxs.com. 5 NS ns3.virtualxs.com.
virtualxs.com. 5 NS ns5.virtualxs.com.
virtualxs.com. 5 NS ns7.virtualxs.com.
Authority
The response has no authority records.
Additional
ns1.virtualxs.com. 5 A 62.129.128.150
ns2.virtualxs.com. 5 A 217.69.8.55
ns3.virtualxs.com. 5 A 62.129.128.151
ns4.virtualxs.com. 5 A 62.129.128.152
ns5.virtualxs.com. 5 A 62.129.128.153
ns6.virtualxs.com. 5 A 62.129.128.154
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0