The expected behavior makes sense. But I think you got

```

order1:order-created

order1:item-1-added-to-cart

order1:item-2-added-to-cart

order1:order-checkout

order1:order-paid

```

because you might have published these messages using the default batch settings. When one message in a batch is nack'ed, all the messages in that batch will be re-delivered.

I tried with `max_messages=1` in the publisher batch setting, and only received:

```

order1:item-2-added-to-cart

order1:order-checkout

order1:order-paid

```