title: React-Redux action.payload is undefined
body: <p>I'm a beginner in Redux. I'm trying to GET a users list, but when I console.log(action.payload) in reducer function it is showing undefined.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>const URL = 'http://localhost:3001/api/'
  
  export function fetchUsers() {
    return (dispatch) =&gt; {
      dispatch(fetchUserRequest());
      return axios.get(`${URL}userdata`)
        .then(response =&gt; response.json())
        .then(userlist =&gt; fetchedUsersSuccessfully(userlist.data))
  
    }
  }
  
  export function fetchUserRequest() {
    return {
      type: 'FETCH_REQUEST',
    }
  }
  export function fetchedUsersSuccessfully(users) {
    return {
      type: 'FETCH_USERS',
      payload: users
    }
  }</code></pre>
  </div>
  </div>
  </p>
  
  <p>This is my reducer </p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>export function users(state = InitialState, action) {
    console.log(action.payload)
    switch (action.type) {
      case FETCH_USERS:
        return [...state, action.payload]
      default:
        return state;
    }
  
  }</code></pre>
  </div>
  </div>
  </p>