ftp.plig.net has no CNAME records.
Question and response
Question
dig ftp.plig.net. NS
Answer
The response has no answer records.
Authority
plig.net. 2361 SOA ns0.plig.net. hostmaster.plig.net. 2025100803 21600 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0