Не работают стили на buttjn в React Native не могу изменить его

import React from 'react';
import { View, Text, Button, StyleSheet } from 'react-native';


const HomeScreen = ({ navigation }) => {
  return (
    <View style={{backgroundColor: 'black' ,flex: 1, alignItems: 'center', paddingTop: 50 }}>
    <View style={{marginBottom: 50}}>
    <Button  title="KHAN TENGRY" color='black' titleStyle={{ fontSize: 50}} onPress={() => navigation.navigate('HanTengri')}/>
    </View>
    <View style={{marginBottom: 50}}> 
    <Button title="SALTANAT" color='black' onPress={() => navigation.navigate('Saltanat')} />
    </View>
    <View>
    <Button title="ORDO" color='black' onPress={() => navigation.navigate('Ordo')} />
    </View>
    <View style={{marginBottom: 50}}>
    <Button title="Screen 4" color='black' style={{ fontSize: 50 }} contentContainerStyle={{ marginTop: 50 }} onPress={() => navigation.navigate('Screen4')} />
    </View>
    </View>
  );
};


export default HomeScreen;