I'm running on Docker w/ image "rabbitmq:3.8.14-management"
Publishing a message with expiration to Q1 (which has these headers declared).
x-dead-letter-exchange: my_exchange
x-dead-letter-routing-key: Q2_routing_key
When the message on Q1 expires, it won't go to Q2 automatically, I have to go on the Get Message(s) button on Q1 and click it, so the trigger happens.

I have used RabbitMQ for a time with similar approaches and this has never happened to me.
Any idea?