I am sure what Artem Bilan has explained here might be one of the reasons for this error:
Caused by: com.rabbitmq.client.AuthenticationFailureException: ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN. For details see the
but the solution for me was that I logged in to rabbitMQ admin page (http://localhost:15672/#/users) with the default user name and password which is guest/guest then added a new user and for that new user I enabled the permission to access it from virtual host and then used the new user name and password instead of default guest and that cleared the error.