ns4.letsdmarc.com has no NS records.
NS records for this zone are defined at letsdmarc.com.
NS records for this zone are defined at letsdmarc.com.
Question and response
Question
dig ns4.letsdmarc.com. NS
Answer
The response has no answer records.
Authority
letsdmarc.com. 1800 SOA clark.ns.cloudflare.com. dns.cloudflare.com. 2399585467 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0