[Samba] error samba backup online

[Trenta sis]

Hi

On a samba 4.10.7 executing a samba backup online I recieve this error:

Partition[DC=ForestDnsZones,DC=domain,DC=com] objects[19/19] linked_values[0/0]
Committing SAM database
INFO 2019-09-23 00:14:25,262 pid:11552
/usr/local/samba/lib/python3.4/site-packages/samba/join.py #1652:
Setting isSynchronized and dsServiceName
INFO 2019-09-23 00:14:25,268 pid:11552
/usr/local/samba/lib/python3.4/site-packages/samba/join.py #1564:
Cloned domain domain (SID S-1-5-21-2047087912-2064396158-1170935892)
ERROR(<class 'IndexError'>): uncaught exception - list index out of range
  File "/usr/local/samba/lib/python3.4/site-packages/samba/netcmd/__init__.py",
line 185, in _run
    return self.run(*args, **kwargs)
  File "/usr/local/samba/lib/python3.4/site-packages/samba/netcmd/domain_backup.py",
line 258, in run
    new_sid = get_sid_for_restore(remote_sam)
  File "/usr/local/samba/lib/python3.4/site-packages/samba/netcmd/domain_backup.py",
line 81, in get_sid_for_restore
    rid = int(res[0].get('rIDNextRID')[0])


command used is
 samba-tool domain backup online --targetdir=/backupi/
--server=server-Ubck --password=pwd

Same command executed on other samba 4.10.7 no errors reported, where
could be the problem?

Thanks