title: Obtaining error while using amazon lex "Invalid Lambda Response: Received invalid response from Lambda"
body: <p>I'm trying to develop a chatbot using AWS Lex. But unfortunately, I'm getting an error while building the chat on Lex. I'm using one intent and 2 slots. For some reason, when the lambda function is connected to the chat, the second value of the slot is saved as <code>null</code>. But when I run it in lambda as a test case, it's successful.
  Right now, all I want to do is show a response message after the details of the slot is entered. </p>
  
  <p>This is my code </p>
  
  <pre><code>public class LexBot implements RequestHandler&lt;Map&lt;String, Object&gt;, Object&gt; {
  
      @Override
      public Object handleRequest(Map&lt;String, Object&gt; input, Context context) {
          // LexRequest lexRequest = LexRequestFactory.createLexRequest(input);
  
          String content = "Request came from the bot: ";
          Message message = new Message("PlainText", content);
          DialogAction dialogAction = new DialogAction("Close", "Fullfiled", message);
  
          return new LexRespond(dialogAction);
      }
  }
  </code></pre>
  
  <p>And this is the error I'm getting in AWS Lex: </p>
  
  <blockquote>
    <p>An error has occurred: Invalid Lambda Response: Received invalid
    response from Lambda: Can not construct instance of Message, problem:
    content must not be blank at [Source:
    {"dialogAction":{"type":"Close","message":{"contentType":"PlainText","some_respond_message":"Request
    came from the bot: "}}}; line: 1, column: 122]</p>
  </blockquote>