bind 9.14.2 query fail for url3569.mail.ebilling.com.tw
The bind version installed by dns server is 9.14.2, and the user will not succeed in dig url3569.mail.ebilling.com.tw.
The message on Log is as follows: Named[32026]: client @0x7fc4500d3ba0 xxx.xxx.xxx.xxx#41401 (url3569.mail.ebilling.com.tw): query failed (failure) for url3569.mail.ebilling.com.tw/IN/A at query.c:6786
If you reduce the bind version to 9.12.4-P1, you can succeed to query.