problem description

the code-push, update has been integrated and released successfully, but the update is not prompted in app

the environmental background of the problems and what methods you have tried

code push is integrated into the project according to the online tutorials, but updates are not prompted in app

related codes

/ / Please paste the code text below (do not replace the code with pictures)

type Props = {};
export default class App extends Component < Props > {

constructor(props){
    super(props);
    this.state={
        label:"update"
    }
}

componentDidMount(){
    codePush.sync({
        updateDialog: {
            appendReleaseDescription: true,
            descriptionPrefix:"\n\n:\n",
            title:"",
            mandatoryUpdateMessage:"",
            mandatoryContinueButtonLabel:"",
        },
        mandatoryInstallMode:codePush.InstallMode.IMMEDIATE,
        deploymentKey: deploymentKey,
    });
}

render () {

return (
  <View style={styles.container}>
    <Text style={styles.welcome}>Welcome to React Native!</Text>
    <Text style={styles.welcome}>you rubbish react-native,motherfucker</Text>
    <Text style={styles.welcome}>Welcome to React Native!</Text>
    <Text style={styles.instructions}>To get started, edit App.js</Text>
    <Text style={styles.instructions}>{instructions}</Text>
  </View>
);

}
}

what result do you expect? What is the error message actually seen?

there is no error prompt