Multiserver vicidial agent login

[renato@aster-lab.com]

all machines are twins (cloned vm).
VERSION: 2.14-697a
BUILD: 190121-2019
© 2019 ViciDial Group

openSUSE 42.3 (x86_64)
VERSION = 42.3
CODENAME = Malachite

All machines were installed using packages.

I have one db server and two vicidial dialers, one operator logs into the first dialer, the other on the second.
I have configured all following the manual at the link : http://www.poundteam.com/downloads/Vici ... v1%201.pdf
The first agent sometimes logs in without problems, other times I got the "there are no available sessions" error.
When the second agent logs into the other dialer, the dialer sends the conference call, when the operator answers the call is immediately dropped.
I then have to forcefully log him out from the web interface since it shows him logged in and in pause.

from that dialer log:
[Nov 7 17:07:53] VERBOSE[16687] dial.c: SIP/300-00000007 answered
[Nov 7 17:07:53] VERBOSE[16687][C-00004a46] pbx.c: Executing [8600051@default:1] MeetMe("SIP/300-00000007", "8600051,F") in new stack
[Nov 7 17:07:53] VERBOSE[16687][C-00004a46] pbx.c: Spawn extension (default, 8600051, 1) exited non-zero on 'SIP/300-00000007'
[Nov 7 17:07:53] VERBOSE[16687][C-00004a46] pbx.c: Executing [h@default:1] AGI("SIP/300-00000007", "agi://127.0.0.1:4577/call_log--HVcauses--PRI-----NODEBUG-----16--------------------SIP 200 OK)") in new stack
[Nov 7 17:07:53] VERBOSE[16687][C-00004a46] res_agi.c: <SIP/300-00000007>AGI Script agi://127.0.0.1:4577/call_log--HVcauses ... -------SIP 200 OK) completed, returning 0

the time on all the three machines is synchronous.

Which data should I send you in order to help me solve this ?

[renato@aster-lab.com]

seems to be solved clearing all conferences on the impacted dialer via web interface