title: Getting error: Missing Authentication Token after AWS API request
body: <p>I am trying to call a Lambda Function through AWS API Gateway.</p>
  
  <p>I've been getting this error when I tried IAM authentication, API Key Authentication and also with no authentication.
  <a href="https://i.stack.imgur.com/NIZdH.png"><img src="https://i.stack.imgur.com/NIZdH.png" alt="enter image description here"></a></p>
  
  <pre><code>{"message":"Missing Authentication Token"}
  </code></pre>
  
  <p>Some people had the same problem due to non existing endpoint. However, I've taken my endpoint directly from the Lambda Function AWS Console.
  <a href="https://i.stack.imgur.com/i69nT.png"><img src="https://i.stack.imgur.com/i69nT.png" alt="enter image description here"></a></p>
  
  <p>I've been trying to open the URL in the Browser and also on the Postman (with and without a header authentication: x-api-key: *****************). 
  <a href="https://i.stack.imgur.com/ke2yZ.png"><img src="https://i.stack.imgur.com/ke2yZ.png" alt="enter image description here"></a></p>
  
  <p>Both responded with above stated error.</p>