Kafka does not reconsume messages after group-id has changed and offset.reset is set to earliest

Question

I am trying to test a feature that requires reconsuming the kafka messages from an earlier offset. I changed the group id into a new one and the auto.offset.reset = "earliest", but that didn't solve the problem at all. On top of this I tried

./kafka-consumer-groups.sh --bootstrap-server etc.etc.gcp.confluent.cloud:9092 --group etc --reset-offsets --to-earliest --all-topics --execute

and I get

Timed out waiting for a node assignment. Call: describeGroups(api=FIND_COORDINATOR).

My third attempt was to simply set up in my application code where I instantiate the consumer the following subscription:

    val subscription = Subscriptions.assignmentWithOffset(new TopicPartition(kafkaConfig.topic, partition), 0)

And... it still does not work.

Any idea what the problem might be?