Redux Persist unable to persist array

I am using Redux Persist in my react native app. My app is a money manager so the user can store expenses and incomes. Therefore I want to have an array called allEntries where all the entries (expense or income) are stored.

My EntriesOverview class where all the entries are shown. I am adding a random new entry in the goToAddNewEntryScreen() methode for demonstration purpose.

import React from 'react';
import {ColorPalette} from '../../Assets/Colors/ColorPalette';
import {Dimensions, Image, StyleSheet, Text, TouchableHighlight, View} from 'react-native';
import {addEntry} from '../../Redux/Actions/counterActions';
import {connect} from 'react-redux';


class EntriesOverviewScreen extends React.Component {

    state: {};
    styles = StyleSheet.create({
        btn_add: {
            position: 'absolute',
            right: 10,
            bottom: 10,
            backgroundColor: ColorPalette.lightMode.primary,
            color: ColorPalette.lightMode.white,
            borderRadius: Math.round(Dimensions.get('window').width + Dimensions.get('window').height) / 2,
            width: Dimensions.get('window').width * 0.15,
            height: Dimensions.get('window').width * 0.15,
            justifyContent: 'center',
            alignItems: 'center',
        },
        btn_add_icon: {
            width: '50%',
            height: '50%',
        },
        background_entries_overview: {
            backgroundColor: ColorPalette.lightMode.white,
            height: '100%',
        },

    });

    constructor(props: Props) {
        super(props);
        this.state = {};
    }

    render() {
        return (
            <View style={this.styles.background_entries_overview}>
                <Text>Entries overview</Text>
                <Text>{JSON.stringify(this.props.allEntries)}</Text>
                <TouchableHighlight
                    style={this.styles.btn_add}
                    onPress={() => this.goToAddNewEntryScreen()}>
                    <Image style={this.styles.btn_add_icon}
                           source={require('../../../MoneyMaster/Assets/Icons/plus_white.png')}/>
                </TouchableHighlight>
            </View>

        );
    }

    goToAddNewEntryScreen() {
        this.props.reduxAddEntry({
            id: -1,
            isExpense: true,
            amount: 0,
            date: new Date('2000-11-25'),
            note: '',
            reoccurring: 'asdf',
            categoryId: 0,
        });
        this.props.navigation.navigate('AddEntryScreen');
    }

}

// Map State To Props (Redux Store Passes State To Component)
const mapStateToProps = (state) => {
    // Redux Store --> Component
    return {
        allEntries: state.entriesReducer.allEntries,

    };
};

// Map Dispatch To Props (Dispatch Actions To Reducers. Reducers Then Modify The Data And Assign It To Your Props)
const mapDispatchToProps = (dispatch) => {
    // Action
    return {
        // Increase Counter
        reduxAddEntry: (entryToAdd) => dispatch(addEntry(entryToAdd)),
    };
};

export default connect(mapStateToProps, mapDispatchToProps)(EntriesOverviewScreen);

My counterAction class

    // Add an Entry
export const addEntry = (entryToAdd) => ({
  type: 'ADD_ENTRY',
  entryToAdd: entryToAdd
});

My entriesReducer class

// Initial State
const initialState = {
  allEntries:[],
  };



// Reducers (Modifies The State And Returns A New State)
const entriesReducer = (state = initialState, action) => {
  switch (action.type) {
    // Increase Counter
    case 'ADD_ENTRY': {
      let updatedAllEntries=state.allEntries.push(action.entryToAdd);
      return {
        // State
        ...state,
        // Redux Store
        allEntries: updatedAllEntries,
      }
    }
    // Default
    default: {
      return state;
    }
  }
};

// Exports
export default entriesReducer;

The strange thing for me is that when I debug it and start the app for the first time the state.allEntries value in my entriesReducer is always 1 eventhough it should be an empty array. Therefore I cant add the entry via the .push methode.Didn't I set the state to an empty array in the entriesReducer? (See image)Initial value is 1 instead of []

Do you have any idea how it could be fixed? Thanks for your help :) And don't be to harsh I am using it the first time ;)

The store

// Imports: Dependencies
import AsyncStorage from '@react-native-async-storage/async-storage';
import {applyMiddleware, createStore} from 'redux';
import {createLogger} from 'redux-logger';
import {persistReducer, persistStore} from 'redux-persist';

// Imports: Redux
import rootReducer from '../Reducers/index';

// Middleware: Redux Persist Config
const persistConfig = {
    // Root?
    key: 'root',
    // Storage Method (React Native)
    storage: AsyncStorage,
    // Whitelist (Save Specific Reducers)
    whitelist: [
        'entriesReducer',
    ],
    // Blacklist (Don't Save Specific Reducers)
    blacklist: [],
};

// Middleware: Redux Persist Persisted Reducer
const persistedReducer = persistReducer(persistConfig, rootReducer);

// Redux: Store
const store = createStore(
    persistedReducer,
    applyMiddleware(
        createLogger(),
    ),
);

// Middleware: Redux Persist Persister
let persistor = persistStore(store);

// Exports
export {
    store,
    persistor,
};

The index

// Imports: Dependencies
import { combineReducers } from 'redux';

// Imports: Reducers
import entriesReducer from './entriesReducer';

// Redux: Root Reducer
const rootReducer = combineReducers({
   entriesReducer: entriesReducer,
});

// Exports
export default rootReducer;