offsite.ctftp.org has no NS records.
NS records for this zone are defined at ctftp.org.
NS records for this zone are defined at ctftp.org.
Question and response
Question
dig offsite.ctftp.org. NS
Answer
The response has no answer records.
Authority
ctftp.org. 3601 SOA dns1.registrar-servers.com. hostmaster.registrar-servers.com. 1773138280 43200 3600 604800 3601
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0