tsters.aboutsters.com has no NS records.
NS records for this zone are defined at aboutsters.com.
NS records for this zone are defined at aboutsters.com.
Question and response
Question
dig tsters.aboutsters.com. NS
Answer
The response has no answer records.
Authority
aboutsters.com. 3601 SOA dns1.registrar-servers.com. hostmaster.registrar-servers.com. 1772534751 43200 3600 604800 3601
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0