Unexpected Publisher Confirmation Behavior

[IlyaGav]

I have two queues: queue1 and queue2. queue2 has two arguments: x-max-length: 10 and x-overflow: reject-publish.
I want to move messages from queue1 to queue2 and it is important for me that no messages get lost.
Here is my code

_model = _connection.CreateModel();

var consumer = new EventingBasicConsumer(_model);
consumer.Received += TransferTargets;

_model.ConfirmSelect();
_model.BasicAcks += OnAcknowledged;
_model.BasicNacks += OnNotAcknowledged;

_model.BasicConsume("queue1", false, consumer);

private void TransferTargets(object sender, BasicDeliverEventArgs e)
{
    var body = e.Body.ToArray();
    var props = _model.CreateBasicProperties();
    _model.BasicPublish("queue2", "", props, body);
}

private void OnAcknowledged(object model, BasicAckEventArgs args)
{
    _model.BasicAck(args.DeliveryTag, false);
}

private void OnNotAcknowledged(object model, BasicNackEventArgs args)
{
    _model.BasicReject(args.DeliveryTag, true);
}

The OnAcknowledged method is called when a message has been delivered to queue2.
The OnNotAcknowledged method is called when a message has not been delivered to queue2.

Thus, if at first there were 100 messages in queue1 and 0 in queue2, then after starting something like this happens: 10 messages are added to queue2 (since there is such a limitation on it), and queue1 can be 95, that is, the OnAcknowledged method was called in total 5 times, although all 10 messages were successfully delivered.

Is this intended behavior or am I doing something wrong?

Environment:
.Net Core version: 3.1
RabbitMQ Server version: 3.8.11
RabbitMQ.Client version: 6.2.1

Sorry, I don't know English well, so I use a translator

[lukebakken]

More than likely, the multiple flag was set on some of the confirms. If so, this means that multiple messages were confirmed at the same time.