next.js @reduxjs/工具包useSelector返回undefined

npm install @reduxjs/toolkit react-redux

// store.js
import { configureStore } from '@reduxjs/toolkit';
import counterReducer from './counterSlice';

const store = configureStore({
  reducer: {
    counter: counterReducer,
  },
});

export default store;

// counterSlice.js
import { createSlice } from '@reduxjs/toolkit';

const counterSlice = createSlice({
  name: 'counter',
  initialState: { value: 0 },
  reducers: {
    increment: (state) => state.value + 1,
    decrement: (state) => state.value - 1,
  },
});

export const { increment, decrement } = counterSlice.actions;
export default counterSlice.reducer;

// pages/_app.js
import { Provider } from 'react-redux';
import store from '../store';

function MyApp({ Component, pageProps }) {
  return (
    <Provider store={store}>
      <Component {...pageProps} />
    </Provider>
  );
}

export default MyApp;

// pages/index.js
import { useSelector, useDispatch } from 'react-redux';
import { increment, decrement } from '../counterSlice';

function Home() {
  const count = useSelector((state) => state.counter.value);
  const dispatch = useDispatch();

  return (
    <div>
      <h1>Counter: {count}</h1>
      <button onClick={() => dispatch(increment())}>Increment</button>
      <button onClick={() => dispatch(decrement())}>Decrement</button>
    </div>
  );
}

export default Home;