title: Code=-1011 "Request failed: internal server error (500)
body: <p>I meet this problem for 2 days,Android app works well with this background interface,but I always receive the 500 error.My code is like this.</p>
  
  <pre><code>AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];
  manager.requestSerializer = [AFJSONRequestSerializer serializer];
  manager.responseSerializer = [AFHTTPResponseSerializer serializer];
  manager.responseSerializer.acceptableContentTypes = [NSSet setWithObject:@"text/html"];
  [manager POST:urlString parameters:self.param.mj_keyValues  success:^(NSURLSessionDataTask *task, id responseObject) {
          ....    
  } failure:^(NSURLSessionDataTask *task, NSError *error) {
          ....
  }];
  </code></pre>
  
  <p>and then,the program goes into the failure block,and I get NSError log like this.</p>
  
  <pre><code>Error Domain=com.alamofire.error.serialization.response Code=-1011 "Request failed: internal server error (500)" UserInfo={com.alamofire.serialization.response.error.response=&lt;NSHTTPURLResponse: 0x7fc26b49a080&gt; { URL: https://training.duapp.com/record_data } { status code: 500, headers {
  Server = openresty;
  Content-Type = text/html;charset=utf-8;
  Vary = Accept-Encoding;
  Content-Language = en;
  Date = Fri, 02 Sep 2016 03:55:00 GMT;
  Content-Encoding = gzip;
  Content-Length = 646;
  Connection = keep-alive;
  }
  }, NSErrorFailingURLKey=https://training.duapp.com/record_data, com.alamofire.serialization.response.error.data=
  </code></pre>
  
  <p>Then I tried to convent the param from NSDictionary to NSData or NSString,and change requestSerializer with it,but all failed with error 500.The format of the param has no error,which is conformed by my background workmate.Can I get any help from you?What should I do?</p>