Apex domains cannot have CNAME records.
Question and response
Question
dig tinet.net. NS
Answer
tinet.net. 5 NS sns.tinet.net.
tinet.net. 5 NS pns.tinet.net.
Authority
The response has no authority records.
Additional
pns.tinet.net. 5 A 213.200.89.94
sns.tinet.net. 5 A 213.200.90.94
pns.tinet.net. 5 AAAA 2001:668:0:1111:0:0:0:1111
sns.tinet.net. 5 AAAA 2001:668:0:2222:0:0:0:2222
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0