Cannot set eager in ES as by ES guide

Elastic Stack Elasticsearch
9

I've found this in logstash log:

[2017-09-07T08:50:36,681][ERROR][logstash.outputs.elasticsearch] Encountered an unexpected error submitting a bulk request! Will retry. {:error_message=>"incompatible encodings: Windows-1250 and UTF-8", :class=>"Encoding::CompatibilityError", :backtrace=>["e:/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.3.8-java/lib/logstash/outputs/elasticsearch/common.rb:153:in `submit'", "org/jruby/RubyArray.java:1613:in `each'", "org/jruby/RubyEnumerable.java:971:in `each_with_index'", "e:/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.3.8-java/lib/logstash/outputs/elasticsearch/common.rb:131:in `submit'", "e:/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.3.8-java/lib/logstash/outputs/elasticsearch/common.rb:91:in `retrying_submit'", "e:/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.3.8-java/lib/logstash/outputs/elasticsearch/common.rb:42:in `multi_receive'", "e:/logstash/logstash-core/lib/logstash/output_delegator_strategies/shared.rb:13:in `multi_receive'", "e:/logstash/logstash-core/lib/logstash/output_delegator.rb:47:in `multi_receive'", "e:/logstash/logstash-core/lib/logstash/pipeline.rb:420:in `output_batch'", "org/jruby/RubyHash.java:1342:in `each'", "e:/logstash/logstash-core/lib/logstash/pipeline.rb:419:in `output_batch'", "e:/logstash/logstash-core/lib/logstash/pipeline.rb:365:in `worker_loop'", "e:/logstash/logstash-core/lib/logstash/pipeline.rb:330:in `start_workers'"]}

And here's my pipeline:

# The # character at the beginning of a line indicates a comment. Use
# comments to describe your configuration.
input {
	beats {
        port => "5044"
    }
}
# The filter part of this file is commented out to indicate that it is
# optional.
filter {
	mutate {
		gsub => ["message", "\|C3\|", "|cir=C3|"]
	}

#	kv {
#		field_split => "|"
#	}
	ruby {
		code => "
			a = event.get('message').split('|').delete_if{|x| !x.match(/=/)}
			a.each {|y| b = y.split('=', 2)
				event.set(b[0].strip, b[1])
			}
			event.set('acronym', event.get('acronym').upcase)"
	}
	mutate {
		gsub => ["date", " ", ";"]
		convert => {"type" => "integer"}
		convert => {"rptPackageStatus" => "integer"}
		add_field => {"country" => "si"}
	}
	date {
		locale => "en"
		match => ["date", "dd.MM.YYYY;HH:mm:ss"]
		timezone => "Europe/Ljubljana"
		target => "date"
	}
	date {
		locale => "en"
		match => ["returnDate", "dd.MM.YYYY"]
		timezone => "Europe/Ljubljana"
		target => "returnDate"
	}
	date {
		locale => "en"
		match => ["firstsignUpDate", "dd.MM.YYYY"]
		timezone => "Europe/Ljubljana"
		target => "firstsignUpDate"
	}
	date {
		locale => "en"
		match => ["lastVisitDate", "dd.MM.YYYY"]
		timezone => "Europe/Ljubljana"
		target => "lastVisitDate"
	}
	date {
		locale => "en"
		match => ["loanDate", "dd.MM.YYYY"]
		timezone => "Europe/Ljubljana"
		target => "loanDate"
	}
	date {
		locale => "en"
		match => ["lastProlongDate", "dd.MM.YYYY"]
		timezone => "Europe/Ljubljana"
		target => "lastProlongDate"
	}
	date {
		locale => "en"
		match => ["reservationDate", "dd.MM.YYYY"]
		timezone => "Europe/Ljubljana"
		target => "reservationDate"
	}
}
output {
	elasticsearch {
        hosts => [ "localhost:9200" ]
        index => "transakcije"
		document_type => "log_transakcije"
    }
#	stdout { codec => rubydebug }
}