TypeError: 'NoneType' is not iterable

[lexghjc]

| 10.07.2018 (18:42:22) |
Traceback (most recent call last):
  File "vk4xmpp/gateway.py", line 767, in sendMessages
    result = func(self, message)
  File "extensions/groupchats.py", line 167, in handleOutgoingChatMessage
    for member in members:
TypeError: 'NoneType' object is not iterable

| 10.07.2018 (20:08:18) |
Traceback (most recent call last):
  File "vk4xmpp/gateway.py", line 767, in sendMessages
    result = func(self, message)
  File "extensions/groupchats.py", line 161, in handleOutgoingChatMessage
    conversation = user.vk.method("messages.getConversationsById", {"peer_ids": MIN_CHAT_ID + chatID})[1]
TypeError: 'NoneType' object has no attribute '__getitem__'