Webhdfs error : Plugin not defined in namespace, checking for plugin file

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1

I am trying to output to webhdfs

my output config is:

output {
webhdfs {
path => 'filepath'
single_file_per_thread => true
host => 'hostname'
port => '50070'
codec => 'json'
}
}

I am getting error;
Plugin not defined in namespace, checking for plugin file

When I do ./bin/plugin list I can see my plugin listed in list.

I am not sure what's wrong with config..