Index not created for elasticsearch with logstash_format on and logstash_prefix set

[vinayakm340]

With just "logstash_format On" it does create an index of value "logstash-". But if a prefix is specified, no index is created and logs do not get indexed.
Using fluent-bit version 1.3.3

Here's what my elastic output config looks like:

  output-elasticsearch.conf: |
    [OUTPUT]
        Name                 es
        Match                 *
        Host                    10.128.241.156
        Port                     9200
        logstash_format On
        Replace_Dots     On
        Retry_Limit         False
        logstash_prefix  myapp

Don't know if it matters but I have tried capitalizing like "Logstash_Format" and "Logstash_Prefix". But it does not work.

[vinayakm340]

With logstash_format & logstash_prefix key removed, it does create an index called "fluent-bit"