connect-mongo latest version return some error in my project I have updated my connect-mongo npm to the latest version 2.0.1 in node v8 its returning some error, if i comment the below code my projects works pretty well if not returning the below error

here is a bit of code 

var session = require('express-session');
var MongoStore = require('connect-mongo')(session);
    app.use(session({
        resave: true,
        saveUninitialized: true,
        secret: '6256346324',
        store: new MongoStore({
            db: global.db
        })
    }));


Error

.then(() =&gt; this.changeState('connected'))
                     ^

TypeError: this.setCollection(...).setAutoRemoveAsync(...).then is not a function
    at MongoStore.handleNewConnectionAsync


modules used in package.json(i have listed only few)

connect-mongo": "^2.0.1",
    "express": "^4.16.2",
    "express-session": "^1.15.6",
    "mongodb": "^2.2.35"


so how can i solve this error?
As per your error it shows you have Express 4.16.2 and mongodb 2.2.35. 

As per NPM Mongo Blog here you can check out the compatibility . As well as for connection integration of Express 4.x.

The sample connection code should be as mentioned below for Express 4.x, 5.0 and Connect 3.x:

const session = require('express-session');
const MongoStore = require('connect-mongo')(session);

app.use(session({
    secret: 'foo',
    store: new MongoStore(options)
}));


For further information see here and here