How the value is undefined , when reading from reducer/ store in react redux?

I am working in react redux. I stored the value in reducer and try to retrieve it. Value is undefined? I am getting the sessionId from url. In App.js, sessionId is having value.

http://localhost:3000?SessionId=89e2ff80-c1d7

import * as types from '../lib/store/action';

const App = () => {
  const dispatch = useDispatch();
  useEffect(function () {

    const params = new URLSearchParams(window.location.search);
    const SessionId = params.get('SessionId');

    if (SessionId != null && SessionId.length) {
      console.log("saving SessionId: " + SessionId);
      dispatch(
        types.updateData({
          SessionId: SessionId
        })
      );
    }
 })
}

Reducer.js

import * as types from './action';

export const initialState = {

    recDetails: {
        name: '',
       country: '',
        city: ''
    },
    SessionId: ''
}

const Datareducer = (state = initialState, action) => {

    switch (action.type) {

        case types.UPDATE__DATA:

            const output = action.payload;

            if (output.recDetails) {

                state.recDetails = output.recDetails;

            }

            if (output.SessionId) {

                state.SessionId = output.SessionId;

            }

            return {

                ...state,

            }

            break;

        default:

            return state;

    }

}

 

export default Datareducer;



Component1.js

import * as types from '../../lib/store/action';

const { SessionId } = useSelector(state => state.app.DataReducer.SessionId);

  const uDispatch = useDispatch();

  useEffect(() => {

      alert(SessionId);}

SessionId is undefined.....

http://localhost:3000?SessionId=89e2ff80-c1d7

Hi, I am reading the sessionId from ur paraameter in app.js. SessionId is showing in app.js and then store in reducer. Readming sessionId in component1 is undefined.