development serve response error code 500 - reactjs

Question

I am new to react native for navigation i am using react-native-router-flux but it returns an error => development server returned response error code 500
I have uninstall and reinstall node modules
My react-native -v is 0.59.9
metro-react-native-babel-preset -v ^0.54.1
react-native-router-flux ^4.0.6
login page
import React, { Component } from 'react'
import { Text, View, StyleSheet, TextInput, TouchableOpacity } from 'react-native'
import { Actions } from 'react-native-router-flux'
export default class Login extends Component {
render() {
return (
<View style={styles.container}>
<View style={styles.header}>
<Text style={styles.headerText}>Sparow</Text>
</View>
<View style={styles.content}>
<TextInput style={styles.usernameInput} placeholder='Enter Your Username' placeholderTextColor='#fff' underlineColorAndroid='transparent' />
<TextInput style={styles.passwordInput} placeholder='Enter Your Password' placeholderTextColor='#fff' underlineColorAndroid='transparent' secureTextEntry={true} />
<TouchableOpacity style={styles.loginBtn} onPress={() => { Actions.Admin() }}>
<Text style={styles.loginBtnText}>Login</Text>
</TouchableOpacity>
</View>
</View>
)
}
}
admin page
import React, { Component } from 'react'
import { View, Text } from 'react-native'
export default class Admin extends Component {
render() {
return (
<View>
<Text>Admin Page</Text>
</View>
)
}
}
routes page
import React, { Component } from 'react'
import { Router, Scene } from 'react-native-router-flux'
import Login from '../screen/Login'
import Admin from '../screen/Admin'
export default class Routes extends Component {
render() {
return (
)
}
}
routes pages
import React, { Component } from 'react';
import Routes from './src/common/Routes'
export default class App extends Component {
render() {
return (
);
}
}