title: Retrofit-2 Content-Type Issue
body: <p>My Api is accepting  Content-Type application/json as headers.
  I set Header perfectly as mentioned in Retrofit Docs. </p>
  
  <pre><code>@Headers("Content-Type: application/json")
  @POST("user/classes")
  Call&lt;playlist&gt; addToPlaylist(@Body PlaylistParm parm);
  </code></pre>
  
  <p>But in Request Log it is Returning Content-Type txt/html.So how i should fix this issue? This api works fine in POSTMAN
  <a href="https://i.stack.imgur.com/aD2Q4.png" rel="noreferrer"><img src="https://i.stack.imgur.com/aD2Q4.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/zXiWl.png" rel="noreferrer"><img src="https://i.stack.imgur.com/zXiWl.png" alt="enter image description here"></a></p>