Recently, while operating our company's own name server, in the early morning of July 2nd, the DNS server suddenly stopped working due to an upgrade issue with the existing Server 2012, so we installed and configured a new server with Server 2019, but the DNS server still does not function. I had an experience where access to the website was blocked for a long time. Therefore, I formatted the server, installed a new one, and configured DNS, but the service continues to not work. I would like to ask if I am doing something wrong with the server 2019 DNS configuration or if I can receive technical advice regarding this.
domain name : myqt.co.kr
Server OS : 2019Win Server standard
ip : name server ns1.myqt.co.kr 61.106.211.21
ns2.myqt.co.kr 61.106.211.82
ns3.myqt.co.kr 218.37.27.60