Gurux.DLMS - Disconnect Error - MT880

Hi Mikko,
I'm trying to read some data from an energy meter Iskraemeco MT880, which is basically working well through the DLMSDirector and also through my python script.
The only thing what is confussing me, that python script is crashing on an error by disconnecting from the meter, the same disconnect with the DLMSDirector is working well. I've compared the request and response from the DLMSDirector and from python script and it looks similar.
Director log:
02:10:04 Parsing AARE reply succeeded.
02:10:06 Disconnect request
02:10:06 Disconnect request
7E A0 08 02 3F 03 53 04 92 7E
02:10:06 02:10:06.298 Sent 7E A0 08 02 3F 03 53 04 92 7E
02:10:06 02:10:06.308 Received 7E A0 1F 03 02 3F
02:10:06 02:10:06.308 Received 3F 73 F2
02:10:06 02:10:06.308 Received 01 9A 06 01 9A 07 04
02:10:06 02:10:06.308 Received 00 00 00 01 08 04 00 00
02:10:06 02:10:06.318 Received 00 01 CC A2
02:10:06
7E A0 1F 03 02 3F 73 F2 4D 81 80 12 05 01 9A 06 01 9A 07 04 00 00 00 01 08 04 00 00 00 01 CC A2 7E
02:10:06 02:10:06.318 Info Closing
02:10:06 02:10:06.352 Info Closed

Python script log:
Index: 2 Value: 246
TX: 02:00:09 7E A0 1A 02 3F 03 54 73 44 E6 E6 00 C0 01 C1 00 03 01 00 20 07 00 FF 03 00 5D 9A 7E
RX: 02:00:10 7E A0 17 03 02 3F 74 6D 63 E6 E7 00 C4 01 C1 00 02 02 0F 00 16 23 07 3E 7E
Index: 3 Value: 1.0, Unit.VOLTAGE
DisconnectRequest
TX: 02:00:10 7E A0 08 02 3F 03 53 04 92 7E
Data send failed. Try to resend 1/3
RX: 02:00:15 7E A0 1F 03 02 3F 73 F2 4D 81 80 12 05 01 9A 06 01 9A 07 04 00 00 00 01 08 04 00 00 00 01 CC A2 7E 7E A0 08 03 02 3F 1F 04 60 7E
Ended. Press any key to continue.
Traceback (most recent call last):
File "C:\Users\iolez\PycharmProjects\Gurux.DLMS.Python\gurux_client_example\main.py", line 121, in main
reader.close()
File "C:\Users\iolez\PycharmProjects\Gurux.DLMS.Python\gurux_client_example\GXDLMSReader.py", line 102, in close
self.readDLMSPacket(self.client.disconnectRequest(), reply)
File "C:\Users\iolez\PycharmProjects\Gurux.DLMS.Python\gurux_client_example\GXDLMSReader.py", line 118, in readDLMSPacket
self.readDLMSPacket2(data, reply)
File "C:\Users\iolez\PycharmProjects\Gurux.DLMS.Python\gurux_client_example\GXDLMSReader.py", line 172, in readDLMSPacket2
raise GXDLMSException(reply.error)
gurux_dlms.GXDLMSException.GXDLMSException: Access Error : Unknown error.

I can of course avoid the program crash with editing the reader, but it still trying to send the disconnect request with timeout 5 secs.

Thank You in Advance