Getting TypeError when returing store data

Question

I am trying to store data from my form component to my store. But when i try to dispatch the action and return the action payload into the state, getting an error which is,

TypeError: state.users is undefined

that action reducer is

export const addUserReducer = (state = { users: [] }, action) => {
  switch (action.type) {
    case "ADD_USER_REQUEST":
      return {
        loading: true,
      };
    case "ADD_USER_SUCCESS":
      return {
        ...state,

        users: [...state.users, action.payload],
      };
    default:
      return state;
  }
};

Redux store for the app is,

import { combineReducers, createStore, applyMiddleware } from "redux";
import { addUserReducer } from "./Reducers/addUserReducer";
import { composeWithDevTools } from "redux-devtools-extension";
import thunk from "redux-thunk";
const finalReducer = combineReducers({
  addUserReducer: addUserReducer,
});
const composeEnhancers = composeWithDevTools({
  // Specify here name, actionsBlacklist, actionsCreators and other options
});

const usersFromStorage = localStorage.getItem("Users")
  ? JSON.parse(localStorage.getItem("Users"))
  : [];
console.log(usersFromStorage);
const initialState = {
  addUserReducer: {
    users: usersFromStorage,
  },
};

const store = createStore(
  finalReducer,
  initialState,
  composeEnhancers(applyMiddleware(thunk))
);

export default store;

I have tried to solve the issue by using many methods but don't know yet that where is the main problem.

Answer 1

In the first case of your switch you should return the other part of the state as well:

case "ADD_USER_REQUEST":
      return {
        ...state,
        loading: true,
      };