Violation of the order queue messages from RabbitMQ.

When receiving an accumulated message queue from RabbitMQ their order is disturbed. Messages come from Rabbit in the correct order but in the stream they are mixed. Stream created as written in the documentation.

DataStream<String> stream = env.addSource(new RMQSource<String>(connectionConfig, queueName, true, new SimpleStringSchema()))
.setParallelism(1);

Example:
In the RabbitMQ message queue is :{message1,message2,message 3,message4...}.
In the flink stream queue messages is :

{message1,message3,message4,message2...}

.