[Samba] Reverse Lookup Zone Not Loaded by DNS Server

[Roy Eastwood]

I have a samba AD domain based on two DCs running samba version 4.14.4 on Debian Buster.    The domain is using Bind DLZ.   When I
open DNS Manager on a Windows domain client both the forward and reverse zones are shown, but if I press F5 and click refresh the
reverse zone shows a red X and the error: Zone Not Loaded by DNS Server.   The zone info looks normal:

samba-tool dns zoneinfo tiger-db 2.168.192.in-addr.arpa -U roy
Password for [MICROLYNX\roy]:
  pszZoneName                 : 2.168.192.in-addr.arpa
  dwZoneType                  : DNS_ZONE_TYPE_PRIMARY
  fReverse                    : TRUE
  fAllowUpdate                : DNS_ZONE_UPDATE_SECURE
  fPaused                     : FALSE
  fShutdown                   : FALSE
  fAutoCreated                : FALSE
  fUseDatabase                : TRUE
  pszDataFile                 : None
  aipMasters                  : []
  fSecureSecondaries          : DNS_ZONE_SECSECURE_NO_XFER
  fNotifyLevel                : DNS_ZONE_NOTIFY_LIST_ONLY
  aipSecondaries              : []
  aipNotify                   : []
  fUseWins                    : FALSE
  fUseNbstat                  : FALSE
  fAging                      : FALSE
  dwNoRefreshInterval         : 168
  dwRefreshInterval           : 168
  dwAvailForScavengeTime      : 0
  aipScavengeServers          : []
  dwRpcStructureVersion       : 0x2
  dwForwarderTimeout          : 0
  fForwarderSlave             : 0
  aipLocalMasters             : []
  dwDpFlags                   : DNS_DP_AUTOCREATED DNS_DP_DOMAIN_DEFAULT DNS_DP_ENLISTED
  pszDpFqdn                   : DomainDnsZones.microlynx.org
  pwszZoneDn                  : DC=2.168.192.in-addr.arpa,CN=MicrosoftDNS,DC=DomainDnsZones,DC=microlynx,DC=org
  dwLastSuccessfulSoaCheck    : 0
  dwLastSuccessfulXfr         : 0
  fQueuedForBackgroundLoad    : FALSE
  fBackgroundLoadInProgress   : FALSE
  fReadOnlyZone               : FALSE
  dwLastXfrAttempt            : 0
  dwLastXfrResult             : 0

Any idea how to debug this will be appreciated.

Thanks

Roy