_senderspf.copernica.com has no NS records.
NS records for this zone are defined at copernica.com.
NS records for this zone are defined at copernica.com.
Question and response
Question
dig _senderspf.copernica.com. NS
Answer
The response has no answer records.
Authority
copernica.com. 60 SOA dns1.proxi.nl. hostmaster.copernica.com. 1767796593 14400 1800 86400 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0