Node js и mongodb не удалось подключиться к серверу [70.32.xx.xx: 27017

Question

Я новичок в изучении nodejs, и я развернул свое приложение api, используя express на a2Hosting для node js app, и я использую mon goose db после всех настроек конфигурации и запуска monodb. сервис на моем хосте VPS, я не могу подключиться к mon goose .connect (URI); и я получил эту ошибку.

MongoNetworkError: failed to connect to server [serverIPXX.XX.XX:27017] on first connect [Error: connect ECONNREFUSED 70.32.24.12:27017
    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1056:14) {
  name: 'MongoNetworkError',
  [Symbol(mongoErrorContextSymbol)]: {}
}]
    at Pool.<anonymous> (/home/perjoaho/nodevenv/PrjoApp/12/lib/node_modules/mongoose/node_modules/mongodb/lib/core/topologies/server.js:438:11)
    at Pool.emit (events.js:209:13)
    at /home/perjoaho/nodevenv/PrjoApp/12/lib/node_modules/mongoose/node_modules/mongodb/lib/core/connection/pool.js:561:14
    at /home/perjoaho/nodevenv/PrjoApp/12/lib/node_modules/mongoose/node_modules/mongodb/lib/core/connection/pool.js:994:11
    at /home/perjoaho/nodevenv/PrjoApp/12/lib/node_modules/mongoose/node_modules/mongodb/lib/core/connection/connect.js:31:7
    at callback (/home/perjoaho/nodevenv/PrjoApp/12/lib/node_modules/mongoose/node_modules/mongodb/lib/core/connection/connect.js:264:5)
    at Socket.<anonymous> (/home/perjoaho/nodevenv/PrjoApp/12/lib/node_modules/mongoose/node_modules/mongodb/lib/core/connection/connect.js:294:7)
    at Object.onceWrapper (events.js:297:20)
    at Socket.emit (events.js:209:13)
    at emitErrorNT (internal/streams/destroy.js:91:8)
    at emitErrorAndCloseNT (internal/streams/destroy.js:59:3)
    at processTicksAndRejections (internal/process/task_queues.js:77:11) {
  name: 'MongoNetworkError',
  [Symbol(mongoErrorContextSymbol)]: {}
}

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код подключения

mongoose.connect("mongodb://XX.XX.XX:27017/perjodb", {useNewUrlParser: true , useUnifiedTopology: true});
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function() {
  // we're connected!
 console.log("DB Connected");

});