authenticateUser(loginCredentials:any){

       var authenticationData = {
            Username : loginCredentials.username,
            Password : loginCredentials.password
        };
        //console.log("authenticationData..",authenticationData);
        var authenticationDetails = new AWSCognito.CognitoIdentityServiceProvider.AuthenticationDetails(authenticationData);
        console.log("authenticationDetails..",authenticationDetails);
        var poolData = {
            UserPoolId : "something", // Your user pool id here
            ClientId : "something" // Your client id here
        };
        //console.log("poolData..",poolData);
        var userPool = new AWSCognito.CognitoIdentityServiceProvider.CognitoUserPool(poolData);
        console.log("userPool..",userPool);
        var userData = {
            Username : loginCredentials.username,
            Pool : userPool
        };
        //console.log("userData..",userData);
        var cognitoUser = new AWSCognito.CognitoIdentityServiceProvider.CognitoUser(userData);
        console.log("cognitoUser..",cognitoUser);

        let self = this;

        try{
        cognitoUser.authenticateUser(authenticationDetails, {
            onSuccess: function (result) {
                console.log('access token + ' + result.getAccessToken().getJwtToken());
                console.log('idToken + ' + result.idToken.jwtToken);

                if(result.getAccessToken().getJwtToken() != null){

                    self.router.navigate(['nexPage']);
                }
            },

            onFailure: function(err) {
                console.log('error message: ' + err);
                alert(err);
            },

        })
        }catch(e){
            console.log("exception:..", e)
        }

   }

EXCEPTION: t.newPasswordRequired is not a function
ORIGINAL STACKTRACE:
TypeError: t.newPasswordRequired is not a function
    at amazon-cognito-identity.min.js:33
    at constructor.<anonymous> (amazon-cognito-identity.min.js:33)
    at constructor.<anonymous> (aws-cognito-sdk.min.js:21)
    at constructor.callListeners (aws-cognito-sdk.min.js:21)
    at constructor.emit (aws-cognito-sdk.min.js:21)
    at constructor.emitEvent (aws-cognito-sdk.min.js:21)
    at constructor.a (aws-cognito-sdk.min.js:21)
    at d.runTo (aws-cognito-sdk.min.js:22)
    at aws-cognito-sdk.min.js:22
    at constructor.<anonymous> (aws-cognito-sdk.min.js:21)
Uncaught Error: t.newPasswordRequired is not a function
    at amazon-cognito-identity.min.js:33
    at constructor.<anonymous> (amazon-cognito-identity.min.js:33)
    at constructor.<anonymous> (aws-cognito-sdk.min.js:21)
    at constructor.callListeners (aws-cognito-sdk.min.js:21)
    at constructor.emit (aws-cognito-sdk.min.js:21)
    at constructor.emitEvent (aws-cognito-sdk.min.js:21)
    at constructor.a (aws-cognito-sdk.min.js:21)
    at d.runTo (aws-cognito-sdk.min.js:22)
    at aws-cognito-sdk.min.js:22
    at constructor.<anonymous> (aws-cognito-sdk.min.js:21)