Pusher Notification received by sender and working in Chrome only. Laravel 5.4 and JQuery

I am using Pusher API for sending notifications in Laravel 5.4 with JQuery. I found out that whenever I send notification from Firefox or Safari...it reaches chrome browser successfully but not vice versa. Another problem is that when I send message, it is being received by me!!! Although I used toOthers() method

My Code is below. Please let me know if you need more info.

Controller Code

broadcast(new SendMessageEvent("hi", \Auth::user()))->toOthers();

Blade

$(function() {
    Pusher.logToConsole = true;
    var pusher = new Pusher('Pusher API key', {
        authEndpoint: 'broadcasting/auth',
        auth: {headers: {'X-CSRF-Token': $('meta[name="csrf-token"]').attr('content')}}
    });
    var channel = pusher.subscribe('private-user-channel.{!! \Auth::user()->UserID !!}');
    channel.bind('App\\Events\\SendMessageEvent', function(data) {
        console.log(data);
    });
});

Event

class SendMessageEvent implements ShouldBroadcast
{
    use Dispatchable, InteractsWithSockets, SerializesModels;

    public $msg;
    public $user;
    public $userid;

    public function __construct($msg, $user) {
        $this->msg = $msg;
        $this->user = $user;
        $this->userid = $this->user->UserID;
    }

    public function broadcastOn()
    {
        return new PrivateChannel('user-channel.1');
    }
}

Channel

Broadcast::channel('user-channel.{userid}', function ($user, $userid) {
    return (int) $user->UserID === (int) $userid;
});

Answer

I found this while searching, if the question is still open :

your event broadcasts everything to userID 1
 return new PrivateChannel('user-channel.1');
but your other users connect to their own channel with their own userID. Change to public channel and test again with your code, the rest seems to be correct.
or 
you should probably use Laravel Echo, which works better than raw pusher, and works with private channels and whatever push notification you got from Laravel :
    Echo.private('{{'App.User.'.Auth::id()}}')
                    .listen('.notify', (e) => {
                        ...
                    })                  
                .notification((notification) => {
                    ...
                });