ex2013.exchange.zetosa.com.pl has no NS records.
NS records for this zone are defined at exchange.zetosa.com.pl.
NS records for this zone are defined at exchange.zetosa.com.pl.
Question and response
Question
dig ex2013.exchange.zetosa.com.pl. NS
Answer
The response has no answer records.
Authority
exchange.zetosa.com.pl. 86400 SOA zetosak80.zetosa.com.pl. dns.zetosa.com.pl. 2021080200 3600 600 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0