com.rabbitmq.client.AlreadyClosedException on langohr 5.2.0 and RabbitMQ server 3.9.11

[shubhang93]

We are constantly getting this error "com.rabbitmq.client.AlreadyClosedException: connection is already closed due to connection error; protocol method: #method<connection.close>(reply-code=504, reply-text=CHANNEL_ERROR - second 'channel.open' seen, class-id=20, method-id=10)" with langohr 5.2.0. We are using a 5 node RabbitMQ cluster running version 3.9.11. We are opening a new channel for every publish, we close the channel immediately after the publish, to prevent race conditions. We saw the second 'channel.open' seen even on the RabbitMQ broker. This error was not present when we were using the RabbitMQ server 3.8.5 with langohr 5.2.0. After upgrading to 3.9.11 we're facing this issue.