Remote storage returning 204 NO CONTENT

I'm trying to save to a remote database from a local grapesjs editor. Although I'm able to hit the endpoint it's giving me a 204 NO CONTENT. 

this is the server I set up: 

 var express=require('express');
 var app=express();
 app.use(bodyParser.urlencoded({ extended: true }))
 app.use(cors());

 app.post('/grapesjs', function (req, res) {
   console.log(req)
  return res.status(200).json({key: 'value'})
});

my grapesjs editor:

 var editor = grapesjs.init({
        height: '100%',
        showOffsets: 1,
        noticeOnUnload: 0,
        storageManager: {
          id: 'gjs-',             
          type: 'remote',          
          autosave: true,        
          autoload: true,         
          stepsBeforeSave: 1,    
          storeComponents: true, 
          storeStyles: true,      
          storeHtml: true,        
          storeCss: true, 
          urlStore: 'http://localhost:8081/grapesjs',
          //urlLoad: 'http://e45d9fde.ngrok.io/grapesjs',
        },
        container: '#gjs',
        fromElement: true,

        plugins: ['gjs-preset-webpage'],
        pluginsOpts: {
          'gjs-preset-webpage': {}
        }
      });