Routing working locally, not on Heroku servers - angularjs

Question

My AngularJS application won't route to /login when accessing /login directly. It will route to /login if I first access / then route from / to /login.
It is working on my local environment but not with Heroku servers. Are there some settings I have to configure on the Heroku server?
I am using angular-ui-router to route to different states throughout my application.
My app.js config snippet looks like this:
angular.module('app', [
angularUiRouter
])
.config(($stateProvider) => {
"ngInject";
$stateProvider
.state("home", {
url: "/",
template: "<home></home>"
})
.state("login", {
url: "/login",
template: "<login></login>"
});
})

Answer 1

Answering my own question.
Since the setup on this application is using MEAN stack, we have to also add routing from server side to client.
For all templates in AngularJS there has to be a routing from Express to AngularJS to index.html
for all templates and routings created in angular we need to get the request and send index.html in response
when we use angularjs stateProvider to route in Angularjs.., we have to also add routing to /dist/index.html from server side.
$locationProvider.html5Mode(true).hashPrefix('!'); has to be defined in app.js on AngularJS side
A snippet of my Server.js file:
var express = require('express');
var app = express();
app.use(express.static(__dirname + '/dist'));
app.get('/', function(req, res){
res.sendFile(__dirname + '/dist/index.html');
});
app.get('/login', function(req, res){
res.sendFile(__dirname + '/dist/index.html');
});