try set up it manually from file settings. that worked for me:
go to dns manager files:
i have there: /www/server/panel/plugin/dns_manager
open there config.json. you will see:
{"domain": ["your.domain"], "listen_ip": "", "NS": {"NS1": "", "NS2": ""}}
fill it with:
{"domain": ["your.domain"], "listen_ip": "", "NS": {"NS1": "ns1.your.domain", "NS2": "ns2.your.domain"}}