Logstash exception/error

Everything I run a logstash file.. for example, ./logstash agent -f twitter.conf..I get the follwoing error message:

{:exception=>Twitter::Error::Unauthorized, :backtrace=>["/opt/Oracle/relk/logstash/vendor/bundle/jruby/1.9/gems/twitter-5.15.0/lib/twitter/streaming/response.rb:21:in on_headers_complete'", "org/ruby_http_parser/RubyHttpParser.java:370:in<<'", "/opt/Oracle/relk/logstash/vendor/bundle/jruby/1.9/gems/twitter-5.15.0/lib/twitter/streaming/response.rb:16:in <<'", "/opt/Oracle/relk/logstash/vendor/bundle/jruby/1.9/gems/logstash-input-twitter-2.2.2/lib/logstash/inputs/twitter/patches.rb:31:instream'", "/opt/Oracle/relk/logstash/vendor/bundle/jruby/1.9/gems/logstash-input-twitter-2.2.2/lib/logstash/inputs/twitter/patches.rb:58:in request'", "/opt/Oracle/relk/logstash/vendor/bundle/jruby/1.9/gems/twitter-5.15.0/lib/twitter/streaming/client.rb:37:infilter'", "/opt/Oracle/relk/logstash/vendor/bundle/jruby/1.9/gems/logstash-input-twitter-2.2.2/lib/logstash/inputs/twitter.rb:128:in run'", "/opt/Oracle/relk/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.4-java/lib/logstash/pipeline.rb:342:ininputworker'", "/opt/Oracle/relk/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.4-java/lib/logstash/pipeline.rb:336:in `start_input'"], :options=>nil, :level=>:warn}

what's going on?

That's why.