MessageQueue deleted messages

Alice is receiving a message via the MessageQueue:

03-21 18:03:19.825 I/MessageQueueManagerImpl: Received message with position  5, expecting 5
03-21 18:03:19.825 I/MessageQueueManagerImpl: Message is in order, delivering

Then a new message is sent by Bob:

03-21 18:05:35.971 I/MessageQueueManagerImpl: Sending message with position 6

But Alice does not get the message, because the MessageQueue is deleting it:

03-21 18:05:36.605 I/MessageQueueManagerImpl: Received message with position  5, expecting 6
03-21 18:05:36.605 W/MessageQueueManagerImpl: Deleting message with duplicate position

Bob sends another message:

03-21 18:05:50.484 I/MessageQueueManagerImpl: Sending message with position 7

This time, Alice gets it, but it still comes in with the wrong position.

03-21 18:05:50.775 I/MessageQueueManagerImpl: Received message with position  6, expecting 6
03-21 18:05:50.775 I/MessageQueueManagerImpl: Message is in order, delivering