Jicofo gives NullPointerException and retry does't happens

sometimes I get this null pointer exception on Jicofo

Jicofo 2019-03-26 04:47:16.948 INFO: [3150] org.jitsi.jicofo.recording.jibri.JibriSession.log() Starting Jibri jibribrewery@internal.auth.meet.example.com/rec-14.cluster.example.com for stream ID: null in room: aaa@conference.meet.example.com
Jicofo 2019-03-26 04:47:17.111 INFO: [38] org.jitsi.jicofo.ChatRoomRoleAndPresence.log() Chat room event ChatRoomMemberPresenceChangeEvent[type=MemberLeft sourceRoom=org.jitsi.impl.protocol.xmpp.ChatRoomImpl@2ffda537 member=ChatMember[178292720@conference.meet.example.com/692ef39a, jid: 692ef39a-5342-4b9d-8169-4a93c910f73b@meet.example.com/343d7618-77f3-4883-8b6b-9e73fa590edb]@577845108]
Jicofo 2019-03-26 04:47:17.111 INFO: [38] org.jitsi.jicofo.ChatRoomRoleAndPresence.log() Owner has left the room !
Jicofo 2019-03-26 04:47:17.112 INFO: [38] org.jitsi.jicofo.JitsiMeetConferenceImpl.log() Member 178292720@conference.meet.example.com/692ef39a is leaving
Jicofo 2019-03-26 04:47:17.112 WARNING: [38] org.jitsi.jicofo.JitsiMeetConferenceImpl.log() Participant not found for 178292720@conference.meet.example.com/692ef39a terminated already or never started ?
Jicofo 2019-03-26 04:47:31.948 SEVERE: [3150] org.jitsi.jicofo.recording.jibri.JibriSession.log() Failed to start Jibri event handler: java.lang.NullPointerException
java.lang.NullPointerException
at org.jitsi.jicofo.recording.jibri.JibriSession.sendJibriStartIq(JibriSession.java:424)
at org.jitsi.jicofo.recording.jibri.JibriSession.start(JibriSession.java:246)
at org.jitsi.jicofo.recording.jibri.JibriSession.retryRequestWithAnotherJibri(JibriSession.java:472)
at org.jitsi.jicofo.recording.jibri.JibriSession.handleJibriStatusUpdate(JibriSession.java:519)
at org.jitsi.jicofo.recording.jibri.JibriSession.processJibriIqFromJibri(JibriSession.java:346)
at org.jitsi.jicofo.recording.jibri.CommonJibriStuff.handleIQRequest(CommonJibriStuff.java:233)
at org.jitsi.jicofo.recording.jibri.OperationSetJibri.handleIQRequest(OperationSetJibri.java:87)
at org.jivesoftware.smack.AbstractXMPPConnection$3.run(AbstractXMPPConnection.java:1154)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Jicofo 2019-03-26 04:47:31.948 INFO: [3150] org.jitsi.jicofo.recording.jibri.JibriSession.log() Failed to fall back to another Jibri, this session has now failed
Jicofo 2019-03-26 04:47:31.948 INFO: [3150] org.jitsi.jicofo.recording.jibri.JibriRecorder.log() Got jibri status off and failure error
Jicofo 2019-03-26 04:47:31.949 INFO: [3150] org.jitsi.jicofo.recording.jibri.JibriRecorder.log() Publishing new jibri-recording-status: in: aaa@conference.meet.example.com

The reason seems to be the failure of receiving JibriIq from jibri if it fails to send the reply back.

JibriIq result = (JibriIq)xmpp.sendPacketAndGetReply(startIq);

This will not do retry simply end recording request with All recorders are busy even though anther jibri is available in the pool.