thumb-for.rharding.com has no NS records.
NS records for this zone are defined at rharding.com.
NS records for this zone are defined at rharding.com.
Question and response
Question
dig thumb-for.rharding.com. NS
Answer
The response has no answer records.
Authority
rharding.com. 3600 SOA dns.rharding.com. support.rharding.com. 1947020969 7200 1800 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0