mail.sprint.com.pl has no NS records.
NS records for this zone are defined at sprint.com.pl.
NS records for this zone are defined at sprint.com.pl.
Question and response
Question
dig mail.sprint.com.pl. NS
Answer
The response has no answer records.
Authority
sprint.com.pl. 3600 SOA ns1.sprintdatacenter.pl. hostmaster.sprint.com.pl. 2023102700 3600 3600 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0