the code is as follows:

//
        client = new Paho.MQTT.Client("47.93.17.20",1883,"869300035506744");//,,Messaging
        //
        client.onConnectionLost = onConnectionLost;//
        client.onMessageArrived = onMessageArrived;//Paho.MQTT.client
        //
        client.connect({onSuccess:onConnect,onFailure:onFailure});
        
 // 
    function onConnect(context){
        console.log("onConnect");
        console.log(JSON.stringify(context));
        // client.subscribe("/luatask/demo/cmd/869300035506744");//
    }
    // 
    function onFailure(errorMessage){
        console.log("");
        console.log(JSON.stringify(errorMessage));
    }
    // 
    function onConnectionLost(responseObject){
        console.log("");
        if (responseObject.errorCode !== 0) {
          console.log("onConnectionLost:"+responseObject.errorMessage);
        }

    }
    //
    function onMessageArrived(message){
        console.log("onMessageArrived:"+message.payloadString);
    }

the error message is as follows:

the first time I use this thing, I don"t know what went wrong even though I made a mistake. I would like to consult all kinds of gods here