Logstash 5.3 Persistent Queue issue

Elastic Stack Logstash
5

My input section (in /etc/logstash/conf.d/logstash-xxx.conf.yml) looks as follows:

input {
    beats {
        id => "beats-input"
        port => 5044
    }

    redis {
        id => "redis-abcd999-filebeat"
        host => "abcd999"
        data_type => "list"
        key => "filebeat"
    }

    redis {
        id => "redis-abcd999-packetbeat"
        host => "abcd999"
        data_type => "list"
        key => "packetbeat"
    }
}

The main Logstash config file contains:

# grep -v '^#' /etc/logstash/logstash.yml

path.data: /MB/Mon/logstash-data
path.config: /etc/logstash/conf.d
queue.type: persistent
path.queue: /MB/Mon/logstash-data/queue
path.logs: /var/log/logstash