mail.idff.edu.do has no NS records.
NS records for this zone are defined at idff.edu.do.
NS records for this zone are defined at idff.edu.do.
Question and response
Question
dig mail.idff.edu.do. NS
Answer
The response has no answer records.
Authority
idff.edu.do. 3600 SOA ns1.contabo.net. hostmaster.contabo.de. 1772567315 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0