_netblocks.hosting.in.th has no CNAME records.
Question and response
Question
dig _netblocks.hosting.in.th. NS
Answer
The response has no answer records.
Authority
hosting.in.th. 299 SOA cantaloupe.hosting.in.th. info.hosting.in.th. 2026022601 10800 3600 1209600 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0