ns.grdns.it has no NS records.
NS records for this zone are defined at grdns.it.
NS records for this zone are defined at grdns.it.
Question and response
Question
dig ns.grdns.it. NS
Answer
The response has no answer records.
Authority
grdns.it. 3600 SOA ns.grdns.cz. admin.grdns.cz. 2020012101 3600 1800 2592000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0