mxtr3.mta.tawk.to has no NS records.
NS records for this zone are defined at tawk.to.
NS records for this zone are defined at tawk.to.
Question and response
Question
dig mxtr3.mta.tawk.to. NS
Answer
The response has no answer records.
Authority
tawk.to. 1800 SOA amy.ns.cloudflare.com. dns.cloudflare.com. 2398278929 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0