pop.serveroffer.net has no NS records.
NS records for this zone are defined at serveroffer.net.
NS records for this zone are defined at serveroffer.net.
Question and response
Question
dig pop.serveroffer.net. NS
Answer
The response has no answer records.
Authority
serveroffer.net. 14400 SOA ns1.serveroffer.net. hostmaster.serveroffer.net. 2019041000 14400 3600 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0