Error: Assertion Failed: You must include an 'id' for member in an object passed to 'push'

I've looked this up on Stackoverflow and still haven't been able to figure out how to get rid of this error. Basically I'm trying to use the Wordpress API and connect it to my Ember App by following this tutorial https://www.codesandnotes.com/ember-js/ember-wordpress/

I'm getting this error:

Error Screenshot

I can't figure out why it is showing up or how to get rid of it. I can't think of anywhere/one else to ask so any help would be really appreciated. Here's my code:

app/router.JS

import Ember from 'ember';
import config from './config/environment';

const Router = Ember.Router.extend({
  location: config.locationType,
  rootURL: config.rootURL
});

Router.map(function() {
  this.route('about');
  this.route('members');
});

export default Router;

app/routes/member.js

import Ember from 'ember';

export default Ember.Route.extend({
  model() {
    return this.store.findAll('member');
  }
});

app/models/member.js

import DS from 'ember-data';
import PostModel from 'ember-wordpress/models/post';

export default PostModel.extend({

});

app/config/environment.js

/* eslint-env node */
'use strict';

module.exports = function(environment) {
  let ENV = {
    modulePrefix: 'doe-site',
    environment,
    rootURL: '/',
    locationType: 'auto',
    EmberENV: {
      FEATURES: {
        // Here you can enable experimental features on an ember canary build
        // e.g. 'with-controller': true
      },
      EXTEND_PROTOTYPES: {
        // Prevent Ember Data from overriding Date.parse.
        Date: false
      }
    },

    APP: {
      // Here you can pass flags/options to your application instance
      // when it is created
    },
    wordpressHost: 'http://wordpress.daughtersofeve.org/'
  };

  if (environment === 'development') {
    // ENV.APP.LOG_RESOLVER = true;
    // ENV.APP.LOG_ACTIVE_GENERATION = true;
    // ENV.APP.LOG_TRANSITIONS = true;
    // ENV.APP.LOG_TRANSITIONS_INTERNAL = true;
    // ENV.APP.LOG_VIEW_LOOKUPS = true;
  }

  if (environment === 'test') {
    // Testem prefers this...
    ENV.locationType = 'none';

    // keep test console output quieter
    ENV.APP.LOG_ACTIVE_GENERATION = false;
    ENV.APP.LOG_VIEW_LOOKUPS = false;

    ENV.APP.rootElement = '#ember-testing';
  }

  if (environment === 'production') {

  }

  return ENV;
};

app/package.json

{
  "name": "doe-site",
  "version": "0.0.0",
  "private": true,
  "description": "Small description for doe-site goes here",
  "license": "MIT",
  "author": "",
  "directories": {
    "doc": "doc",
    "test": "tests"
  },
  "repository": "",
  "scripts": {
    "build": "ember build",
    "start": "ember server",
    "test": "ember test"
  },
  "devDependencies": {
    "broccoli-asset-rev": "^2.4.5",
    "ember-ajax": "^3.0.0",
    "ember-cli": "~2.15.1",
    "ember-cli-app-version": "^3.0.0",
    "ember-cli-babel": "^6.3.0",
    "ember-cli-dependency-checker": "^2.0.0",
    "ember-cli-eslint": "^4.0.0",
    "ember-cli-htmlbars": "^2.0.1",
    "ember-cli-htmlbars-inline-precompile": "^1.0.0",
    "ember-cli-inject-live-reload": "^1.4.1",
    "ember-cli-qunit": "^4.0.0",
    "ember-cli-shims": "^1.1.0",
    "ember-cli-sri": "^2.1.0",
    "ember-cli-uglify": "^1.2.0",
    "ember-data": "~2.15.0",
    "ember-export-application-global": "^2.0.0",
    "ember-load-initializers": "^1.0.0",
    "ember-resolver": "^4.0.0",
    "ember-source": "~2.15.0",
    "ember-welcome-page": "^3.0.0",
    "ember-wordpress": "^0.1.7",
    "loader.js": "^4.2.3"
  },
  "engines": {
    "node": "^4.5 || 6.* || >= 7.*"
  }
}