当第一个成员发送加入会议的请求时，会创建会议，并且附加的会话会收到“会议创建”和“添加成员”，但是当第二个成员加入同一会议时，第一个成员会收到“ del-member”和“ conference-destroy”以及会议再次为第二个成员创建。
这是什么原因？
下面是FreeSWITCH日志
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] switch_ivr.c:623 sofia/erlang/xxxxmemberone@10.3.65.89:5080 Command Execute conference(X2C3DTAbRqAj66yPjxHwmw+flags{})
rMXAICB6XqrXXhA1ESEjnQ EXECUTE sofia/erlang/xxxxmemberone@10.3.65.89:5080 conference(X2C3DTAbRqAj66yPjxHwmw+flags{})
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CALL_UPDATE to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_commands.c:4788 (sofia/erlang/xxxxmemberone@10.3.65.89:5080) State Change CS_CONSUME_MEDIA -> CS_EXECUTE
2020-09-16 12:49:32.287033 [DEBUG] handle_msg.c:101 Sending bgapi reply to xxx@xxx02
2020-09-16 12:49:32.287033 [DEBUG] mod_conference.c:3057 using channel sound prefix: /usr/share/freeswitch/sounds/en/us/callie
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] conference_member.c:1690 Raw Codec Activation Success L16@8000hz 1 channel 20ms
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] conference_member.c:1737 Raw Codec Activation Success L16@8000hz 1 channel 20ms
2020-09-16 12:49:32.287033 [DEBUG] mod_conference.c:220 Setup timer success interval: 20 samples: 160
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] switch_core_codec.c:223 sofia/erlang/xxxxmemberone@10.3.65.89:5080 Push codec L16:100
2020-09-16 12:49:32.287033 [ERR] switch_core_video.c:2256 This function is not available, libpng not installed
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CODEC to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CUSTOM to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] conference_loop.c:1140 Setup timer soft success interval: 20 samples: 160 from codec PCMA
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] switch_core_codec.c:248 sofia/erlang/xxxxmemberone@10.3.65.89:5080 Restore previous codec PCMA:8.
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CUSTOM to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CODEC to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] switch_core_state_machine.c:584 (sofia/erlang/xxxxmemberone@10.3.65.89:5080) Running State Change CS_EXECUTE (Cur 4 Tot 3272)
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE_COMPLETE to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] switch_core_state_machine.c:650 (sofia/erlang/xxxxmemberone@10.3.65.89:5080) State EXECUTE
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_sofia.c:198 sofia/erlang/xxxxmemberone@10.3.65.89:5080 SOFIA EXECUTE
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] switch_core_state_machine.c:328 sofia/erlang/xxxxmemberone@10.3.65.89:5080 Standard EXECUTE
rMXAICB6XqrXXhA1ESEjnQ EXECUTE sofia/erlang/xxxxmemberone@10.3.65.89:5080 park()
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event PRIVATE_COMMAND to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_STATE to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] switch_ivr.c:980 Codec Activated L16@8000hz 1 channels 20ms
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_PARK to attached session rMXAICB6XqrXXhA1ESEjnQ
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.287033 [DEBUG] switch_ivr.c:623 sofia/erlang/0002_udayas@10.3.65.89:5070 Command Execute break()
y37p-L0uDNlf5yDfPhx6Ow EXECUTE sofia/erlang/xxxxmembertwo@10.3.65.89:5070 break()
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE to attached session y37p-L0uDNlf5yDfPhx6Ow
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE_COMPLETE to attached session y37p-L0uDNlf5yDfPhx6Ow
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.287033 [DEBUG] mod_erlang_event.c:157 Sending event PRIVATE_COMMAND to attached session y37p-L0uDNlf5yDfPhx6Ow
2020-09-16 12:49:32.307008 [DEBUG] mod_conference.c:799 Write Lock ON
2020-09-16 12:49:32.307008 [DEBUG] mod_conference.c:802 Write Lock OFF
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.307008 [DEBUG] switch_ivr_play_say.c:1942 done playing file /opt/ivr/prompts/0002/IVRSystemPrompt::ringtone.wav
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.307008 [DEBUG] switch_rtp.c:7229 Correct audio ip/port confirmed.
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.307008 [DEBUG] mod_erlang_event.c:157 Sending event PLAYBACK_STOP to attached session y37p-L0uDNlf5yDfPhx6Ow
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.307008 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE_COMPLETE to attached session y37p-L0uDNlf5yDfPhx6Ow
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.327026 [DEBUG] mod_erlang_event.c:157 Sending event PRIVATE_COMMAND to attached session y37p-L0uDNlf5yDfPhx6Ow
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.327026 [DEBUG] switch_ivr.c:623 sofia/erlang/xxxxmembertwo@10.3.65.89:5070 Command Execute conference(X2C3DTAbRqAj66yPjxHwmw+flags{})
y37p-L0uDNlf5yDfPhx6Ow EXECUTE sofia/erlang/xxxxmembertwo@10.3.65.89:5070 conference(X2C3DTAbRqAj66yPjxHwmw+flags{})
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.327026 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE to attached session y37p-L0uDNlf5yDfPhx6Ow
2020-09-16 12:49:32.347017 [DEBUG] mod_conference.c:3057 using channel sound prefix: /usr/share/freeswitch/sounds/en/us/callie
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.347017 [DEBUG] conference_member.c:1690 Raw Codec Activation Success L16@8000hz 1 channel 20ms
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.347017 [DEBUG] conference_member.c:1737 Raw Codec Activation Success L16@8000hz 1 channel 20ms
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.347017 [DEBUG] switch_core_codec.c:223 sofia/erlang/xxxxmembertwo@10.3.65.89:5070 Push codec L16:100
2020-09-16 12:49:32.347017 [DEBUG] mod_conference.c:220 Setup timer success interval: 20 samples: 160
2020-09-16 12:49:32.347017 [ERR] switch_core_video.c:2256 This function is not available, libpng not installed
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.347017 [DEBUG] mod_erlang_event.c:157 Sending event CODEC to attached session y37p-L0uDNlf5yDfPhx6Ow
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.347017 [DEBUG] mod_erlang_event.c:157 Sending event CUSTOM to attached session y37p-L0uDNlf5yDfPhx6Ow
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.347017 [DEBUG] conference_loop.c:1140 Setup timer soft success interval: 20 samples: 160 from codec PCMU
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.347017 [DEBUG] conference_loop.c:1292 Outbound conference channel answered, setting CFLAG_ANSWERED
y37p-L0uDNlf5yDfPhx6Ow 2020-09-16 12:49:32.367019 [DEBUG] mod_erlang_event.c:157 Sending event CUSTOM to attached session y37p-L0uDNlf5yDfPhx6Ow
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.367019 [DEBUG] switch_ivr.c:623 sofia/erlang/xxxxmemberone@10.3.65.89:5080 Command Execute break()
rMXAICB6XqrXXhA1ESEjnQ EXECUTE sofia/erlang/200020392007780@10.3.65.89:5080 break()
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.367019 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.387019 [DEBUG] mod_erlang_event.c:157 Sending event CHANNEL_EXECUTE_COMPLETE to attached session rMXAICB6XqrXXhA1ESEjnQ
rMXAICB6XqrXXhA1ESEjnQ 2020-09-16 12:49:32.387019 [DEBUG] mod_erlang_event.c:157 Sending event PRIVATE_COMMAND to attached session rMXAICB6XqrXXhA1ESEjnQ
3b197cd8-f7c7-11ea-b345-05e6082de1e2 2020-09-16 12:49:33.127012 [DEBUG] mod_erlang_event.c:157 Sending event CUSTOM to attached session 3b197cd8-f7c7-11ea-b345-05e6082de1e2